A Sweet (Potato) Harvest!

Despite the summer’s drought, this was a great growing season for sweet potatoes. While they are tropical plants and typically associated with being grown in more southern climates, many varieties do well here in New England. They are not related to potatoes but rather, morning glories.

Sweet potato flowers look like morning glories as they are part of that family. Photo by dmp2022.

Not only are sweet potatoes a highly nutritious vegetable, they are easy to grow with few pests in this area. Native to the Americas, sweet potatoes contain high levels of vitamins A and C along with supplying iron, potassium, and dietary fiber. An average sized sweet potato only has around 120 calories.

To harvest a good crop, sweet potatoes need a growing season of between 90 and 120 days depending on the variety. My favorite choice is ‘Beauregard’, which matures in 90 days so if we have a colder than average spring, there is still enough time for a sizeable harvest. ‘Georgia Jet’ in another variety that matures in 90 days and ‘Centennial’ in 100. ‘Bush Porto Rico’ takes a little longer to mature (110 days) but is a more compact variety for smaller gardens and containers. All of these varieties have dark orange flesh but for those looking for something different, sweet potatoes can be found with white, yellow and even purple flesh.

Rule number one when growing sweet potatoes is to give them enough room to run. Once the warm weather hits, the vigorous vines cover a sizeable area. I planted 12 slips in a 6 by 15-foot bed and they still rambled into neighboring beds and out into the lawn area.

Sweet potato vines escaping from the garden. Photo by dmp2022.

While potatoes are started with pieces of the actual tuber, sweet potatoes are started from slips, which are basically cuttings off a mother plant with a small amount of root and a few leaves. The sweet potatoes that we eat are the plant’s tuberous roots.

Sweet potato slip. Photo by dmp2022.

Being of southern origin, sweet potatoes can take the heat and even some drought and need to be grown in a sunny site with well-draining soil. If your soil is on the sandy side, so much the better as well-aerated soils promote the formation of more roots. I grow them in a slightly raised bed but have seen directions for creating small mounds to grow them in if your soil is rocky or compacted.

Not many garden centers carry edible sweet potato slips or plants so your best bet would be to order them from a seed/plant company online. Order early, like in January, to ensure you get the variety you want. A dozen slips will easily feed a family of four and usually that is the smallest amount one can order. When the slips come in, place them in a container of water for a day or two to hydrate them before planting.

Hopefully the arrival of your sweet potato slips will coincide with good planting weather. Ideally they should be planted 3 or 4 weeks after the last spring frost or when the soils warms up to 65 degrees F. I have held them for a week all together in a pot with some soilless media in a bright but not full sun window.

Plant the slips deep enough to cover the roots, usually 6 inches deep or so. Space plants about 30 inches apart to allow plenty of room for tuberous root formation. Plants could be watered in with a high phosphorus liquid fertilizer. Keep them moist for the first two weeks to ensure good root establishment. After that, water when the soil dries out and no rain is predicted. Avoid planting in soils that have recently had manure added. Do not overfertilize with nitrogen as plants may produce lots of foliage and not a lot of sweet potatoes.

Harvest after the frost starts to blacken the foliage. Cut back the vines and gingerly start digging with a trowel or small shovel about 18 inches from plant crowns. The crowns can be tugged upon and if the soil is loose, where the sweet potatoes are is often obvious and they can be removed from the soil.

Sweet potato foliage blackened by frost. Photo by dmp2022.

While some sources say not to wash them, this year with all the rain made them pretty muddy so I washed them off and set them in the sun to dry.

Fresh dug sweet potatoes covered with mud. Photo by dmp2022.

Try not to bruise them and store in a humid place around 55 degrees F. Curing at 80 degrees and high humidity for 10 days is suggested to improve storage but it is hard to find these conditions during a New England fall. I just let them dry and wipe off any soil that was clinging to them and store in a bin in my cool basement. My sweet potatoes really varied in sizes with some being quite large – probably just need one for a sweet potato pie.

Some huge sweet potatoes! Photo by dmp2022.

I learned my lesson in past years not to leave them in the ground too long after the frost kills back the vines. Voles and slugs also find sweet potatoes delectable and will start nibbling on them if not harvested in a timely fashion.

Portions of my sweet potatoes were feasted on by slugs or voles. Photo by dmp2022.

So if you are looking for something different to grow as you peruse 2023 seed/plant catalogs, why not try sweet potatoes. Except for some feeding damage on the potatoes, I did not have any other insect or disease problems. After they were established, I just mulched and did not add any additional water this year and got quite a good size harvest, despite the summer’s drought.  

Dawn P.

 

Getting Ready for Spring Planting? Reduce Seed-borne Diseases with a Hot Water Seed Treatment!

As we head into March, we begin to prepare for spring gardening once again! This includes tasks like wrapping up any necessary winter pruning and ordering seeds to plant for the upcoming year. With internet shopping of seed catalogues being more accessible than ever, many people will find that they can purchase the exact crop and cultivar they want with the push of a button. Varieties can even be filtered by yield or disease resistance.

Other people however, may wish to use heirloom seeds from their own or a neighbor’s garden, or organic seeds that aren’t pre-screened or treated for seedborne diseases. Although gardeners may have grown to anticipate some losses with these seeds due to seedborne diseases, a solution exists for many in the form of a hot water seed treatment (HWST).

What is a hot water seed treatment (HWST)?

It is exactly what you might expect: hot water is used to kill pathogens present on the surfaces of seeds before they are planted. For some types of plant diseases, this is an effective means to reduce disease incidence and give young plants the opportunity they need to become established and grow well. Seeds are “prepped” for treatment by first being submerged in a lukewarm water bath of 100 degrees Fahrenheit for 10 minutes. The seeds can then be moved to a bath set at the “treatment temperature”, which varies by crop type. After treatment, the seeds are gently, but thoroughly dried-off so they do not germinate prematurely.

Pure distilled water is pumped into the water baths.

Our equipment can precisely regulate water temperature!

An aquarium air bubbler helps move water and decrease damage to seeds that may overheat by staying still

The bubbler is kept at the base of the water bath using some removable weights (washers!)

The seeds are ready for the plunge!

Quick, gentle drying using only a fan is important so seeds are not damaged.

HWST process in photos. Photo credit: Nick Goltz, DPM

What types of seeds can undergo HWST?

Many types of seeds can undergo HWST for disease mitigation, but generally it is performed on small and hardy seeds. Large, fleshy seeds such as beans or pumpkin seeds may benefit from HWST in terms of disease reduction, but are more sensitive to damage from the hot temperatures and may have accordingly lower germination rates. Therefore, we only recommend HWST with seeds whose germination rates have been shown to be minimally impacted by the high temperatures. Additionally, seeds that have already been treated with HWST or fungicides, or those that have seed coatings (often these are a different color than uncoated seeds), should not be treated.

What diseases will HWST target?

There is ongoing research into what diseases can be successfully mitigated with HWST. Treatment efficacy varies by crop, but generally the diseases are those that will show up shortly after germination, while the plants are still seedlings. The UConn Plant Diagnostic lab and other university extension services that offer HWST will list the types of plants recommended for treatment and the diseases that can be controlled. Visit https://plant.lab.uconn.edu/hwst/ to find out more. The UConn PDL is funded, in part, by the state of Connecticut and the USDA through IPM Extension Implementation and National Plant Diagnostic Network grants.

Nick Goltz, DPM

 

Vegetable Gardens Sprout During Tough Times

A quick review of our soil tests from the 2020 spring season so far saw a greater than 10 percent increase in samples submitted for vegetable gardens. Perhaps it is just coincidental but this may also reflect a way many of us are dealing with these tough economic times due to the COVID-19 pandemic. For whatever reason, be assured that the UConn Soil Nutrient Analysis Lab remains open to accept your soil samples.

My grandparents (may they rest in peace) lived through the Great Depression years of 1929 into the 1930’s. When they came to this country as European immigrants they brought with them, among other items, basic food growing skills. Despite the relatively small lots in their Buffalo, NY backyards, they managed to grow a magnificent harvest of fruits and vegetables which were used fresh and preserved, and distributed among family and neighbors alike. I thought it might be interesting to review some other economically challenging times Americans have been faced with over the past century to see how local food gardening figured into coping with financial hardship.

As citizens left the agriculturally-based countryside and moved into urban areas, less food was grown by individual persons and instead they frequented the neighborhood grocery store for their fruits and vegetables and other staples. In times of good fortunes, their urban wages covered the cost of groceries. During economic downturns when unemployment became more widespread, many became impoverished and unable to buy enough food to feed their families. One such time in this country was during the 1890’s. It was during this period that ‘Pingree’s Potato Patches’ came into being.

Haze S. Pingree was the mayor of Detroit and requested that owners of vacant lots allow the unemployed to grow vegetables on their land. This saved the city money because less city aid was necessary to help the unemployed. It saved the taxpayers money because their taxes didn’t go up as high as they would have if they had to purchase food that wasn’t being produced locally. But the real benefit was to the unemployed who now had, at least temporarily, a feeling of self-respect and accomplishment, not to mention the fresh produce and opportunities for exercise and to socialize with other city residents.

Planting a ‘Liberty Garden’ was the patriotic thing to do during the First World War. Food production in Europe had dropped off precipitously because the farmers had left their fields to go to war and also, growing crops was not easy to do in war zones. It fell to the Americans to grow and supply food for the 120 million residents of the Allied countries. In 1917, the National War Garden Commission was founded by Charles Lathrop Park and there were more than 3 million garden plots by the end of that year. Americans were encouraged to plant gardens to feed ourselves and our allies, reduce fuel and transportations costs and share in this tremendous burden of war. Posters, cartoons, press releases and pamphlets served to educate gardeners on growing and preserving the harvest, and foster national interest in growing food.

Dig for Victory by artist Peter Fraser from Wikipedia.org

President Woodrow Wilson further encouraged the ranks of the food growing public saying, “Everyone who creates or cultivates a garden helps…..This is the time for America to correct her unpardonable fault of wastefulness and extravagance.” By 1918, there were over 5 million garden plots!

The 2009 economic crisis had many likening it to the Great Depression, which started in1929 and lasted well into the late 1930’s. Hundreds of thousands lost their jobs in America but it too had worldwide financial repercussions. Relief gardens, sometimes referred to as welfare gardens or subsistence gardens were set up with governmental assistance to provide food and work opportunities. The greater governmental involvement probably sprung from the fact that it wasn’t the individual who was responsible for this massive economic failing but rather the inadequacies of the system as a whole.

Recreated Victory Garden at Strawberry Banke. Photo by dmp, 2007

It took several years to set up the gardening programs during the Great Depression but by 1933, most were resolved. Also non-governmental organizations participated in the war to combat hunger. Those who owned their own plot of land were encouraged to use it for food production and leave the community garden spots for those less fortunate. Both seeds and gardening supplies were distributed to the gardeners. Some farmers criticized the program believing that it was contributing to overproduction.

From: http://www.livinghistoryfarm.org

With President Franklin D. Roosevelt’s ‘New Deal’ policy in 1933, over 3 billion dollars of aid was given to work garden programs being distributed by the Federal Emergency Relief Administration. Increased relief dollars, not surprising, came with stricter eligibility restrictions and not everyone in need was able to obtain assistance through these gardening programs. Finally, in 1935, funding was cut for these relief garden programs although some gardens, for example, those in New York City, continued to be cultivated. Working in the relief garden programs was no longer seen as an opportunity to improve one’s circumstances but simply as a food source for those less fortunate.

Recreated Victory Garden at Strawberry Banke, Photo by dmp, 2007

Just a few short years later, with the start of World War II, ‘Victory Gardens’ began sprouting up in response to the War Food Administration’s National Victory Garden Program. Some of these gardens were vestiges of WWI or depression era gardens but many were recent arrivals. Goals for these gardens included lessening the demands on commercial vegetable growers and processors so more food would be available to feed our troops, reducing food transportation needs to conserve energy for war efforts, increase self-sufficiency by preserving food for future needs, and to boost American morale by participating in healthy exercise and nutritious eating.

Victory garden sign, Photo by dmp,2020

Even Eleanor Roosevelt rallied to the cause having a Victory Garden installed on the grounds of the White House although apparently it was, at first, a source of distress to the USDA as they feared is would have a negative impact on the food industry. Nonetheless, the USDA did come round and ended up distributing information about food gardening in their public services booklets.

Efforts to cultivate Victory Gardens were enormously successful with 5.5 million gardeners participating in 1942. Seed companies had been remarking about the increase in vegetable seed sales this past year but it was nothing compared to over 300 percent increase they saw back then! Estimates by the USDA are that the Victory Gardens were producing 9 to 10 million pounds of produce which is about 44 percent of the fresh fruits and vegetables consumed at that time!

The war ended. Growing one’s own food was not high on the list of priorities as attention turned to rock and roll, teen idols like Elvis Presley, blue collar jobs, poodle skirts, drive ins, Betty Crocker casseroles and production of Baby Boomers.

While no governmental figure, that I am aware of, is encouraging growing one’s own food, the increased demand for seeds, fruit plants and chicks seems to indicate a real concern that food items may be limited as this pandemic eludes control. Folks with plant cultural or pest questions are welcome to contact the horticulturists at the UConn Home & Garden Education Center at ladybug@uconn.edu. We’re here to help you grow.

Stay safe.

Dawn P.

 

Wisteria

One of my favorite plants in our yard is a large wisteria that wends its way through and around our back deck. Planted in the early 2008 this woody, non-native climbing vine was slow to flower. Although a hardy, fast-growing plant, wisteria usually doesn’t produce flowers until it establishes itself and matures so it was a few years before the first blooms appeared in May of 2011, the image on the left. The center image is from May, 2013 and the image on the right is from the same perspective but in May of 2017.

May, 2011

May, 2013

May, 2017

In early May, before most of the foliage leafs out, the flowers will begin to open, starting at the base and gradually working towards the tip. The 6-12” long drooping racemes of wisteria bloom from basal buds on last year’s growth of wood. It will continue to bloom through the summer when it has full sun and well-drained soil.

 

Wisteria vines can become very heavy and need a strong structure such as a trellis, arbor, pergola, or in our case, a deck to provide support. The twining of the stems can be used to identify the species, depending on whether they twine clockwise or counter-clockwise when viewed from above. Our wisteria twines counter-clockwise so it is a Wisteria sinensis, Chinese wisteria. Wisteria that twines clockwise is Wisteria floribunda, Japanese wisteria.

I usually prune it in the early spring when I also give it a low nitrogen-fertilizer. If it sends out unruly new growth during the spring and summer I just break them off by hand. Likewise, with any adventitious shoots that appear at the base of the plant. It’s a low-maintenance plant otherwise with practically no pests or diseases. The bees and other pollinators love it and I saw a hummingbird visiting it this week. One of the few pests that are ever on it are Japanese beetles.

As you can see by the oval white egg on the surface of its green thorax this beetle has been parasitized by a tachinid fly, Istocheta aldrichi. These tiny flies attach a solitary egg to the Japanese beetle. It will hatch a week later and then the tiny larvae will burrow its way into the body to feed. The larvae will consume the beetle from the inside causing its ultimate death, exiting the body to pupate. If you see a Japanese beetle with one of these eggs on it, let it be. It is already on death row and the new fly that it is nourishing will go on to parasitize other beetles in the future.

As I walked past the wisteria earlier this week I noticed bees among its beautiful pendulous violet flowers. I took out my phone to get a picture and as I focused on the buzzing bee I noticed how the individual blooms of wisteria are so like the blossoms of the different beans in the vegetable garden.

Like bean and pea flowers, the blossoms of wisteria are zygomorphic. ‘Zygomorphic’ means that the flower is only symmetrical when divided along one axis, in this case vertically, unlike the radial symmetry of a flower such as a daisy which is the same on either axis. Clockwise from the top these are the blossoms of a wisteria , a purple sugar snap pea, a pole bean, and a yard-long bean.

Wisteria

Yard-long bean

Pole bean

Snow pea

Wisteria and beans share many traits with the almost 18,000 other species in the Fabaceae family, also known as Leguminosae, making it the third largest family of flowering plants. Grown world-wide, this group contains trees, shrubs, vines, and herbs that bear fruit called legumes. Many legumes are grown to eat, such as the edible pods of freshly-picked snow and sugar peas and beans, the edible seeds of peas and peanuts, or dried pulses such as lentils, chickpeas, soybeans, beans, and lupin.

I never connected the ornamental lupin, Lupinus polyphyllus, that grow in our flower beds with the salty lupini beans, Lupinus albus, that accompany many antipasto platters. But when you look at the seed pods of an herbaceous lupin the similarity to other legume seed pods becomes apparent. The images are, clockwise from the upper left, wisteria, lupin, purple snow pea, sugar snap peas, and yard-long beans.

Wisteria

Lupin

Purple snap pea

Yard-long bean

Sugar snap pea

Fun fact about another legume: in a method called geocarpy, the seed pods of peanuts develop underground. This gives rise to its other moniker, the groundnut. Post-fertilization, the yellowish-orange peanut bloom sends out a ‘peg’ that grows down to the soil where the ovary at the tip matures into a peanut seed pod.  Like most other legumes, peanuts have nitrogen-fixing bacteria called rhizobia in their root nodules. This capacity to take inert atmospheric nitrogen from the soil means legumes require less nitrogen fertilizer. When the plants die they can improve soil fertility for future crops by releasing that fixed nitrogen.

Scarlet runner beans

Any home gardener can benefit from growing legumes, whether they enjoy the beautiful blooms, the healthful benefits derived from eating these high protein and fiber foods or to enrich their garden soil for future plantings.

Susan Pelton

UConn Home & Garden Education Center, 2018

All images by Susan Pelton

 

What a Little Rain Can Do

This summer has been, as they say, one for the books. High temperatures that went on for weeks and limited rainfall certainly did a number on our gardens, containers, and flower beds. Many calls to the Home & Garden Education Center were from gardeners bemoaning the sad state of affairs. Plants were stunted, didn’t set flowers or dropped them early when they did, leaves were scorched looking, and in general plants just performed poorly.

What a relief when the temps dropped into the 80s and rain actually fell in measurable quantities. Plants rebounded, lawns revived, and gardens began to produce once again. My window boxes and some hanging containers did not quite survive though and I refilled most of them this week with some beautiful flowering vinca and a plant that is new to me, evolvulus, a member of the morning glory family that produces tiny, bright blue flowers that last just a day.

The squash plants that I thought were done for have now taken over their areas and are producing copious blossoms and fruit. I am happy to see that the Powdery mildew resistant variety (Success PM) has proven its worth as there are very few signs of the disease.

The squash bugs however have yet to give up the fight. There are still egg masses every few days and the odd grouping of nymphs that I am not sorry to say do not last long once I have spotted them.

The cucumbers and the eggplants are loaded with blossoms and have started bearing fruit. The tomatoes, which hadn’t suffered as much as some of the other plants, have been slow to ripen but they can continue to produce into October if they are covered at night.

I had moved some potted basil plants into a shady area a few weeks back and they have shown their appreciation by filling out nicely. I detect pesto in our near future! A second planting of arugula looks great as does the kale.

 

 

And we are not the only ones that are enjoying the kale. This differential grasshopper was munching away happily, not even caring that I was filming him. This species of grasshopper (Melanoplus differentialis) has been known to do some substantial damage to crops such as grains, hay, and alfalfa, especially during hot, dry periods which increase the likelihood of survival of the nymphs and adults. They will also feed on annuals such as sunflowers and perennials including one of their favorites: ragweed. Maybe they are not all bad. They don’t cause enough damage in a home garden to warrant insecticidal control.

 

A striped cucumber beetle (Acalymma vittatum) was also enjoying the kale even though the cucumber plants were not far away. The adult feeds on the foliage and the larvae feed on the roots but the biggest problem that they bring with them is the bacterial wilt known as Erwinia tracheiphila which can be fatal to cucurbits. The feeding of the adult beetle opens wounds in the plant but it is through the frass (excrement) that the bacteria enter the vascular tissues of the plant. As the bacteria multiply they block the xylem and prevent water and nutrients from reaching the shoots and leaves. The striped cucumber beetle is definitely a bigger concern than the grasshopper or squash bugs as they move so quickly that it is hard to just squish them out of existence like I do with the squash bug nymphs.

Over on the asparagus fern a red milkweed beetle (Tetraopes tetrophthalmus) stood out brightly against the delicate ferns. As with other insects that also feed on milkweed the red milkweed beetle accumulates alkaloid toxins in their flesh that protect it from predators. The black spots against that bright red-orange background are the insect equivalent of a large ‘Do Not Eat” sign. These can be picked off and dropped into a container of soapy water. Don’t use a spray or systemic insecticide on the milkweed as it will harm the beneficial insects that also visit, especially the Monarch butterfly.

The Asian lady beetle has that same bright coloring and also uses a defensive chemical to deter predators. Some humans are allergic to this foul-smelling liquid that can be exuded from their legs. But this one was very busy doing what ‘ladybugs’ do best, munching on some aphids that were on the underside of a squash leaf.

 

The lady beetles may start to congregate both inside and outside of houses and can be a nuisance. Visit our fact sheet for information on the Asian lady beetle if you experience an infestation and consider the non-lethal ways to remove them, keeping in mind how beneficial they will be in next year’s garden. Although the nighttime temperatures can start to dip into the 50s as we progress into September the garden will enjoy the still warm days into October.

Susan Pelton

All images and videos by S. Pelton

 

 

Tomato Troubles: Blossom End Rot, Yellow Shoulders and Cracking

 

Cracks in tomatoes, black rotten spots on the bottom of tomato fruit, and a hard yellow or white area on the inside walls of ripe tomatoes are all physiological problems, not caused by insects or disease.  It is a sad sight for gardeners investing so much time and energy to see the actual fruits of their labor turn into less than perfect tomatoes.

 

Cracked Tomato

Let’s start with why tomatoes crack. Higher moisture levels after a dry period, such as lots of rain after a time of drought, will cause the inside cells to swell and grow faster than the outside skin will grow, resulting in splitting of the skin. To prevent cracking, keep soil evenly moist by watering, and use a mulch to prevent evaporation and keep soil cooler. Cracked tomatoes are still very edible, but not so pretty. Sometimes the cracks are deep, allowing rot to happen inside the meat of the fruit. Plan to use split tomatoes before rotting happen.

Blossom End Rot, photo by Joan Allen.

Blossom end rot is expressed by a black, sunken area on the bottom, the blossom end, of the tomato. It is caused by a lack of calcium reaching the fruit. The soil could be lacking calcium which can only be determined by having a soil test done for nutrient levels. UConn does a basic soil test for $12.00 at soiltest.uconn.edu. New England is not usually lacking calcium in its soil, it is more likely the cause of blossom end rot is an interruption in the delivery of calcium from the soil to the fruit via water uptake. This is caused by irregular watering, letting the soil dry out, then watering or having a big rain event. Occasionally, high levels of potassium or magnesium fertilizers will compete with calcium uptake by the plants. Only use a balanced fertilizer to avoid an excess of individual nutrients and provide even water levels to the soil to avoid blossom end rot. Portions of the tomato not rotted are also still edible if you cut away the bad part.

Yellow Shoulders, hort.purdue.edu

Yellow shoulders disorder occurs on the top part of the tomato when areas never turn red, but stay yellow. The flesh underneath can be tough and corky. It can occur only on the top portion or can occur as a grey or white wall just under the skin around the whole fruit.This problem is caused by a number of different circumstances or combinations of them. We do know it is a problem at the cellular level that happens very early as the fruit is forming.  Cells in the area are smaller and not aligned normally, and the green chlorophyll areas do not develop red pigment. Causes are thought to be high temperatures over 90 degrees F at time of fruit formation, and possible pH levels over 6.7, and potassium, magnesium and calcium competition among each other. Again, a balanced fertilizer is needed.

Tomato with white walls, yellow shoulders, photo by Becky M.

 

The take away message for all of these physiological problems are to have an adequate soil fertility and soil pH without over fertilizing, and have even soil moisture. Hope for summer temperatures to stay at or below 90 degrees F and your harvest baskets will be full of beautiful, delicious tomatoes.

-Carol Quish

 

 

Time to Squash the Vine Borer

Now is the time when a small pest that has the potential to do a large amount of damage will be hatching. I am speaking of the Squash Vine Borer, the larval stage of the clearwing moth Melittia cucurbitae, an insect so synonymous with the squash family that it has cucurbit in its name.

The adult clearwing moth, unlike many other moth species, is diurnal and is therefore active during the day. With its orange abdomen and clear wings it is often is mistaken for a wasp. The adults are now emerging from the soil where they have over-wintered as pupae. Anecdotally it is said that the squash vine borer lays its eggs when the blue chicory is in bloom and a drive along any of our major interstates will confirm that it is indeed blooming now. (image by Chris Evans, University of Illinois, Bugwood.org)

 

The eggs, which are very small, are laid singly at the base of the stalks near the soil. This will make it easier for the newly-hatched larvae to enter the stalk. Seven to ten days later the larvae, which are white with a brown head, will emerge from the reddish-brown eggs and within hours instinctively burrow into the stem to begin feeding.(image by Clemson University – USDA Cooperative Extension Slide Series, Bugwood.org)

At this point symptoms will begin to appear starting with a wilting of the plant that recovers in the evening but progressing to a plant that does not revive in the evening or after watering. There may also be small entry holes visible at the base of the stem and sawdust-looking frass (waste). The larvae feed inside the stem for a little over two weeks, reaching 1” in length, at which time they exit the plant, burrowing 1-6” into the soil where they will pupate until next spring. I plant my cucurbits in upside-down coco coir liners that have a 2″ diameter hole in the bottom (now the top).

The small opening and the protective coco coir make it easier to cover the base of the plant with row cover cloth and harder for the larvae to get to the soil to pupate. In warmer climates there may be two generations per year so we are fortunate that Connecticut only experiences one generation each summer.

It is almost impossible to control the larvae once they have entered the stems. If Bt (Bacillus thuringiensis) is applied to the plant tissue that is near the area where the larvae will hatch then they will feed on the residues prior to entering the stalk. Bt is a common soil-dwelling bacterial organism that forms crystals of insecticidal toxins called Cry proteins or crystal proteins. When consumed by the larvae, the Cry proteins undergo a series of chemical changes to the point that they paralyze the intestinal tract and the insect starves to death. Also good to know is that mammals have no toxic or allergic reactions to Bt, it only affects species in the orders Coleoptera, (beetles), Diptera (flies), Hymenoptera (ants, bees, sawflies, and wasps), Lepidoptera (moths and butterflies, and nematodes. Bt can also be injected into the stem where squash vine borer activity is suspected making it the only treatment that may work once the borer is inside. Additionally, normal exposure rates of Bt will not harm bees so that is good news for our pollinators.

Butternut squash, cucumbers, and melons are not as susceptible to the squash vine borer as summer squash, pumpkins, and Hubbard squash, so plant the former varieties if you don’t want to deal with the borer. There are some practices that can be used if, like me, you can’t imagine a summer without freshly picked and grilled summer squash or a winter without home-canned ratatouille.

The best protection is to prevent the clearwing moth from laying its eggs in the first place. Row covers placed during the egg-laying period starting in mid-June can be highly effective, just be sure to remove when the blossoms are ready for pollination (or leave them on and hand-pollinate). If possible, don’t plant in the same location as the prior year. If it’s not possible to rotate, at least turn over the soil at the end of the season to expose the pupae to the freezing temperatures of winter.

For more information and control measures please check out our: Squash Vine Borer fact sheet.

Susan Pelton

 

 

Let’s Get Planting!

Late March and early April in Connecticut are the time of year that we gardeners dream about through the long, cold winter. The temperatures are on the rise, the days have lengthened, the soil is workable, and even if we do receive a snowfall it generally doesn’t last for long. The Lenten Rose (Hellebore) has bloomed and the crocus, grape hyacinth, daffodils are in their glory, soon to make way for the tulips which will follow. Yellow daffodils paired with the deep purple-blue of the grape hyacinth is one of my favorite combinations.

The pussy willows have come out and the forsythia is in bloom which means that it is the anecdotal time to put down the crabgrass preventer. The pre-emergent herbicide needs to be applied and watered in before the crabgrass seeds that were dropped last year germinate. Please visit our page on Crabgrass Control for more information on this yearly bane of homeowners.

For me this time of year is about planning this year’s vegetable garden and starting the growing season. It starts with plotting out the area that we have allotted for our vegetable garden (its 15’ x 25’) which includes four raised beds that are 3’ x 5’ each. There are many ways to do a garden plan. The simplest way, and the way that I started some years ago, is to put pencil to paper and sketch out a rough drawing.

The next step up is to use graph paper to plot out the actual footage available. This is the manner that I have progressed to over the years. With pencil, ink, and colored pencils I draw the placement of this year’s plantings. I refer to prior year’s plans so that I can rotate varieties among the beds as much as possible although I don’t have a very large space. There are several established perennial plantings, such as asparagus, strawberries, raspberries, rhubarb, and chives that do not get rotated.

These crops are placed around the perimeters of the garden, mostly to the east and south, where they will not block the sun from other plantings. The asparagus spears are just starting to emerge, the chives are growing, and the rhubarb was a perfect size to divide and replant.

A recent post on our UConn Home & Garden Education Center  Facebook page shared a link to many vegetable garden planners that can be found on-line ranging from the very simple to those that allow you to enter your actual plot size, vegetable varieties and succession plantings. There is even an app!

So, plan in place, it’s time to start planting. There are so many crops that enjoy a cool weather start such as peas, spinach, kale, arugula, radishes, beets, bok choy, and carrots. I have been working with my daughter Hannah on some plans for garden beds that her early education class will be working on this spring. In doing research on some classroom-appropriate experiments I came across one that compares the growth rate of seeds germinated (prior to planting) vs. un-germinated (direct sown). I usually soak beet seeds before they are planted but this year I germinated all of the varieties that are planted in the early spring, laying the seeds out on a damp paper towel and covering them with another damp towel.

Just a side note, did you know that each beet ‘seed’ is actually a hard shell that encloses 3 seeds? As they sprout you can not only see three distinct seedlings (the row on the left in the image below) but the colors reflect the variety of beet also, whether red or yellow.

Within days most of the seeds were well-sprouted and I planted them in the garden in their selected spots. It will be interesting to see if this gives them a head-start and if Hannah’s class gets similar results. They will also be running an experiment that starts seeds in solutions of differing pH levels from base to acidic to see what seeds prefer. If you would like to know the pH level of your garden soil and what your crops require then a soil sample to the UConn Soil Nutrient Analysis Laboratory.

One thing to keep in mind when planting is done as a classroom activity is the length of the available growing season. There is little point in planting vegetables that will need care and be ready to harvest during the summer months when school is not in session. Our choices therefore were cool-weather plants that would be ready to harvest before school dismisses for the summer. Among these are snow peas that will mature in 60 days, Indian Summer spinach (35 days), Little Finger carrots (65 days), lettuce, arugula and spinach (35-40 days), Early Wonder beets (60 days) and Cherry Belle radishes that will be ready to harvest in just 22 days.

Just think about it. In a little more than a month we can be enjoying a freshly picked, tasty salad that is the harbinger of more good things to come!

Susan Pelton

All images by Susan Pelton

 

 

Blossom End Rot of Tomatoes

August is supposed to be the month of non-stop tomatoes. Occasionally things go awry to interrupt those carefully laid spring visions of bountiful harvests, sauce making, and endless tomato sandwiches. Blossom end rot can appear to put an end to the crop production by damaging the ripening and developing fruits. We are seeing and receiving calls in a  higher number than more recent years from backyard gardeners complaining about black rotten spots on the bottom of their tomatoes. The spots start as a thickened, leathery spot which sinks in, always on the bottom of the fruit.

Blossom end rot on tomato, ohioline.osu.edu

Blossom end rot can also occur on peppers.

Blossom end rot on peppers, photo taken by client

Blossom end rot is a physiological condition due to lack of calcium. Calcium is needed by plants for  proper growth in all functions of cell making, but is most important for cell walls. Without enough calcium either in the soil, or if delivery of uptake of dissolved calcium in soil water is interrupted, cell division stops in the fruit. Tomatoes are especially sensitive to a lack of calcium.

Interruptions in uptake of calcium can happen by repeated cycles of soil drying out, receiving water, then drying out again. Times of drought and hot, humid weather make the problem worse. Plants lose water through their leaves through a process called transpiration, similar to the way we sweat. They then pull up water through their roots. If there is not enough soil moisture, plants wilt. This break is water delivery also limits calcium delivery. Tomato, and to a lesser degree pepper fruits, respond by developing rot on the bottom, the end where the blossom was before the fruit started growing.

High humidity and multiple cloudy days reduces transpiration, thereby reducing water uptake. This leaves plants not able to bring up new calcium rich water to the site making new cells of the fruit. Another interruption of delivery of calcium resulting in blossom end rot. This means that even if you have enough calcium in the soil and you water the soil regularly, the plants still may not be able to move enough calcium to where it is needed to produce a fruit.

Have a soil test done to make sure soil has enough calcium and that pH levels are around 6.5 so nutrients are most readily available. Water regularly so plants receive 1 to 2 inches of water per week for optimum growth. Feel the soil around the root zone to make sure water is soaking in and reaching the roots. Humidity and cloud cover are not obstacles we can help the plant with, so monitor the fruit for rot spots and remove. There are calcium foliar sprays which claim to deliver calcium to be absorbed by the leaves for use by the plant. This won’t help after the rot has already developed, but may help deter future spots on still developing tomatoes.

-Carol Quish

 

 

 

 

Happenings In The Vegetable Garden This Week

Lots of happenings in the vegetable garden this week as things start to take off. Yellow summer squash and zucchini are starting to produce fruits. The first flowers that appeared were male, identified by their long stems holding the blossom. Female flowers have a small squash shaped ovary at the blossom base, that if becomes pollinated, will grow into a full-sized squash.If the pollination of the female flower does not happen, the tiny squash will drop off. Female flowers appear about a week after the first male flowers are put out by the plant.

Female squash blossoms with a fruit behind it. Photo by C.Quish

Male squash blossom is on the long stem. Photo by C.Quish

At the first appearance of blossoms, the squash vine borer also was seen. The adult is a clear winged moth that lays her eggs on the hollow stems both varieties. The egg hatches into a larva tunneling into the center of the vine, feeding on the inside of the stem and blocking the transmission of water to the leaf and all plant material above their feeding site. The result will be wilting of the plant.

Squash vine borer adults, Jeff Hahn photo, UMN.edu

Control measures are trapping adults, preventing egg laying, and killing larva once stem is invaded. Trap adults by placing a yellow bowl or container filled with soapy water in the garden. Adults are attracted to the color yellow, will fly to the container where they become trapped in the soapy water. Check for eggs on the stems daily and crush any you find. Some folks wrap stems with aluminum foil to create a barrier to egg laying. If larva are found inside the stem, use a hat pin to poke through the stem into the larva to cause death of the insect while the stem will not be harmed much. Another way is to use a knife to slice lengthwise into the stem, dig out the larva, put the stem sides back together and cover with soil. The plant often recovers. Chemical control includes applying insecticide to the base and stems of the squash plant. This will kill the larva before it has a chance to burrow into the stem. Registered insecticides again the squash vine borer are neem, Surround, permethrin and pyrethrins. Always follow pesticide label directions.

Kale, bok choi and Swiss chard are keeping us in greens. The dreaded small caterpillars are starting to appear. Imported cabbage moth, crossed striped caterpillar and the cabbage looper are all common in Connecticut. Insecticidal soap, Bt and spinosad are organic control measures that work well on the early stages of the caterpillar. Apply at recommend label times to keep up with any new hatchings. Be aware of any white moths flitting around the cole crops to alert you to egg laying and the subsequent caterpillar presence.

Cross-striped cabbagworm larva (Evergestis rimosalis).
Clemson University USDA Cooperative Extension Slide Series, http://www.insectimages.org

Cabbage looper larva (Trichoplusia ni) and feeding damage.
David Cappaert, Michigan State University, http://www.insectimages.org

Tomatoes, peppers and cucumbers were planted late as my garden had to wait for other responsibilities to happen before planting took place this year. All seem to be slow due to the colder spring soils, so maybe this is a blessing in disguise and I will have an extended harvest. I plan on planting spinach, lettuce, kale and carrots during August for later season crops. Colder hardy varieties will be selected and I will use row covers later to protect from frosts.

– Carol Quish