August 2022


The soil is a reservoir that holds water for plants. It is important for recharging groundwater by allowing rainfall to infiltrate and filter through the soil into the water table. This happens because the soil is a porous media where the spaces in the soil (pores) are either filled with air or water. The capacity of soil to hold water determines your watering practices in order to provide continued sufficient water for plant growth depending on the drought resistance of your plants. However, not all soils are equal in this capacity.

Bare soil dark with organic matter. Photo by dmp2022.

Field capacity is an important characteristic of soil because it represents the maximum amount of water that a soil can hold. The main soil properties that affect the field capacity of a soil include soil texture, organic matter and compaction.

Soil texture refers to the proportions of sand (0.05-2.0 mm), silt (0.002-0.05 mm), and clay (smaller than 0.002 mm) in the soil. A higher proportion of the larger sand size particles, the more coarse a soil is. Sandy, coarse textured soils have lower field capacity. This is because the greater amount of large particles leads to larger pores from which the water can quickly drain. On the other hand, fine textured soils comprised of the smaller soil particles have a greater amount of small pores that can hold water better, leading to a greater water holding capacity of these soils. However, not all the water held by soils can be used by plants. Some water is very tightly held in the soil and not able to be taken up by plants.

Figure shows general relationship between soil how plant available water capacity (easily available water plus slowly available water) is impacted by soil texture (source: The Nature and Properties of Soils by Ray R. Weil and Nyle C. Brady).

Plant available water holding capacity represents the water retained in soil between field capacity and the wilting point, in another word, it represents the amount of water retained in soil that can be taken up by plants. Even though soils that have high clay contents (such as clay loam, clay) can hold more water, they hold the water tightly so less water is available for plants than silt loam or a sandy loam. The question is, how do we improve soil texture for improved plant available water holding capacity? Unfortunately, changing soil texture of a field is not a viable option unless you introduce foreign soils to the field. Fortunately, there are other options available to improve plant available water holding capacity.

Organic matter is another portion of the soil that holds water. The higher the organic matter content, the more water the soil can hold. Increasing organic matter can increase the field capacity significantly. Increased soil organic matter content improves soil structure which results in increased infiltration, therefore, increasing plant available water. The strategies to increase soil organic matter includes growing cover crops, adding manure, compost or biochar or mixing in leaf mold, peat moss or coir. Avoid disturbing the soil by refraining from overtilling, either manually or with a rototiller.

Till either manually or with a rototiller only when necessary. Photo by dmp2012

Compaction reduces the plant available water holding capacity of a soil. This is because compaction reduces porosity which in turn decreases a soil’s field capacity. Compaction also crushes large pores into smaller pores which leads to a greater proportion of the water being held more tightly by soils. As a result, compaction results in less water available for plants to take up. Also, when a soil is compacted, it becomes harder for roots to penetrate. This can lead to less volume of soil for roots to access to water that is held below than the compacted layer. Stay off soils when they are wet, avoid overtilling, and make defined walking paths through garden areas or perhaps use stepping stones so as not to compact your soils.

Salt content is another soil characteristic that impacts availability of water to plants. Soils that are high in salt concentration tend to have higher wilting points that results in less water for plants to take up. This is more of a problem in the dry regions of the US where salt accumulation is mainly a result of natural soil formation processes and irrigation. In our soils, the salt level can be elevated in areas that have been overfertilized.

In addition to adopting practices that can increase the plant available water holding capacity, there are other practical options for reducing water loss from soil. Mulching is an effective practice to reduce evaporation loss of water. There are many sources of mulches available in the market such as hay, straw, wood chips, bark or cocoa shells. Gardeners can also use untreated lawn clippings.

Haiying Tao, Ph. D.

Emelie Swackhamer, Penn State University, Bugwood.org    

Credit: PA dept of Agriculture

There has been an invasion on Connecticut’s southwest border and the invader is expected to take over the state in approximately two years. It will threaten agricultural businesses, nurseries and homeowners and could cause billions of dollars in damage while devastating the landscape. Who is this invader? It is commonly called the spotted lanternfly, and every Connectican should be concerned. 

The spotted lanternfly, Delicate Lycormala, (SLF), is a sap-feeding plant hopper native to China. It is believed to have entered this country as an egg mass stuck to a shipment of stone sent to Berk’s County, Pennsylvania in 2012. Since then, Pennsylvania’s agriculture, vineyards, forests, nurseries and residential areas have all suffered serious damage from this invasive pest.

Credit: Ichydogimages

Sadly, the SLF started making its way into Connecticut in 2021. The CT Agricultural Experiment Station immediately issued a quarantine order to slow the spread of this pest. While this will not stop the advance of the SLF, it is hoped a sufficiently aggressive effort by all affected will slow it down long enough to find a treatment that will control and, with any luck, eradicate this pest . 

Credit: Ichydogimages

But, what is a spotted lanternfly and why is it so important to stop it from invading our state?  This beautiful looking plant hopper affects fruit trees, grapes, hops and ornamental trees.  The nymphs (immature stage of the SLF) and the adults feed on the sap from trees and vines causing them to weaken. Then, excretions from the SLF, called honey dew, stick to the leaves, which causes black sooty mold to grow, reducing the plant’s ability to photosynthesize properly.  For agricultural crops, this will reduce yields and weaken trees and plants further, eventually destroying them.

In addition to destroying plants it can wreak havoc on everything from lawn furniture,to sidewalks, to the sides of buildings, to car tires,  to anything else outside making it a sticky mess.

Credit Victoria Smith, CASE

Lawrence Barringer, PDA, Bugwood.org

Research is actively under way at Penn State in collaboration with Cornell University using various anti-SLF agents; they haven’t yet produced sufficiently consistent results to qualify as an SLF control.

What can you do to help? Right now, the Connecticut Agricultural Experiment Station is conducting a “call to action” for the state’s citizens. They urge everyone to report any sightings of this invasive pest.

If you spot an SLF, kill it right away and report it on CT Agricultural Experiment Station’s website, by filling  out a brief form along with a photo at:  https://portal.ct.gov/CAES/CAPS/CAPS/Spotted-Lanternfly—SLF

Marie Woodward, Horticultural Consultant

Tobacco barn

“Keep calm because August is here.” – Unknown

This may be remembered as the year of drought and oppressive heat. Trees and shrubs are showing signs of stress in parts of the state that missed isolated rainfall events, and many fern species in shaded woods have turned brown. Animals are having a full-time job looking for water and birds are at my bird baths all day long getting a drink. Even though it has been a dismal year weather-wise, there are still a lot of interesting things to see when we are out and about.

Common buckeye butterfly on a wild Rudbeckia flower

The native trailing wild bean, Strophostyles helvola, may be common but easily overlooked as populations can be sparse in their habitat. Flowers are pink and the lower keel has a dark purple projection that curls upward like the raised trunk of an elephant. Leaflets are in threes, with bluntly lobed leaves.

Groundnut, Apias americana is another native pea family vine that blooms in August. The flowers of this plant are clustered and very fragrant and they are visited by many of the smaller native bees that can climb inside.

Groundnut flower cluster

In a field with mowed paths I recently observed a good number of the non- native wool carder bees on the flowers of birdsfoot trefoil. This plant is also member of the pea family and has yellow, puffy, slipper-like flowers.

Wool carder bee with head inside birdsfoot trefoil flower

This same field had thousands of grasshoppers that took flight as I walked along the path. Most seemed to be what I have nicknamed the ‘plus and minus” grasshopper, for the tiny patterns on the wings. There was also a seed bug on Queen Anne’s lace that had interesting vein patterns on its wing tips.

Wing tip vein patterns on seed bug

A little eft of the red spotted newt put in an appearance in a golf course fairway a couple of days after a heavy rain, as is their habit. They come out of the woods looking for food, seem to lose their way getting back to the safety of leaf litter and often need a rescue from mowers.

Eft returned to the safety of the woods

Katydids are another late summer insect that may be heard rather than seen. Their loud rasping ‘night music’ begins in late July and is joined by crickets by August.  

 Common true katydid

This morning I was out just before sunup and heard odd noises on the siding of the garage. I saw two dark forms moving up the siding and needed a flashlight to discover that they were gray tree frogs. Must have been some insects there they were hunting, I guess.

Gray tree frog climbing up the house

Tobacco is being harvested and hung in barns now. Any barn is something of interest to me, and tobacco barns in use are just one type I like. Any barn with a flag, too, for some reason. I am also a fan of playful or interestingly creative farm signs.

Something bad must have happened

I am hoping we come to the end of this drought in time for water supplies and plants to recover before winter. Just saw a monarch laying an egg on milkweed that hadn’t succumbed to aphid damage or drought, so that is something good. As you travel about outdoors, at any time of year, do not forget to look up. You may miss something…

Pamm Cooper

Gardeners are no strangers to insect pests. While typically a mild nuisance, insect damage can weaken plants and lead them to be more susceptible to disease. There are even times when insect feeding alone can damage a plant sufficiently to kill it, so noticing when insect feeding is occurring and the different types of insect feeding damage are important skills for gardeners to keep in their tool belt.

The Nibblers

We all know these. Nibblers cause the most obvious type of feeding damage – the holes and leaves munched away. Insects that commonly cause this type of damage are grasshoppers (order Odonata), caterpillars (order Lepidoptera), immature sawflies (order Hymenoptera), and others with mandibles (mouthparts) made for chewing. Usually, the most economic way to deal with these pests is to simply pick them off of your plants when you observe them.

Although many types of Lepidopteran pests simply chew through leaves, some remove leaves (and needles!) to form casings needed for pupation and metamorphosis, as is the case with these bagworms (likely Thyridopteryx ephemeraeformis). Photo credit: Nick Goltz

The Borers and Miners

This subgroup of the nibblers are tougher to deal with. While they have similar chewing mouthparts, they are the usually found within their plant hosts. Borers are usually beetles that chew through woody plants (order Coleoptera), though sometimes caterpillars (order Lepidoptera) chew through herbaceous plants (such as the squash vine borer, Melittia cucurbitae). Leafminers may also be Lepidopterans, though most are immature flies (order Diptera). They are best managed by using a systemic insecticide – one that is taken up by the plant and distributed throughout. As with all insecticides, be sure to apply following label instructions and not while pollinators are visiting the plant.

Beetles have bored through this wood. Some species burrow deeply into the plant’s vascular tissue while others burrow along the bark, forming tunnels called “galleries”. Both types of damage can be seen on this log in the Sonoma forest. Photo credit: Nick Goltz

The Piercing-suckers

These insect pests have a modified mouthpart called a stylet, which works like a straw. Piercing-sucking pests use their stylets to suck plant “juices” from soft tissue, stunting growth and causing leaf distortion, spotting, and reduced vigor. Common insects that cause this type of damage are aphids and whiteflies (both are order Hemiptera). Insects in this group are more likely to transmit viruses than those in most other orders.  

Aphids (order Hemiptera, family Aphididae) are the bane of many a gardener! They reproduce quickly and often target young, supple tissue like new leaves and flower buds. Above is a photograph of aphids feeding on my roses earlier this year. Photo credit: Nick Goltz

The Gall-makers

Some insects, such as thrips (order Thysanoptera) can cause some similar disfigurement damage as those mentioned above, but may also cause the formation of galls, a type of unusual growth on plant tissue caused by insect feeding and/or the production of unusual plant growth hormones by the insects. The larvae of some wasps (order Hymenoptera) can cause the production of really interesting galls. There are non-insect pests, such as mites (class Arachnida), and certain types of fungi and bacteria that can also cause galling. Most of the time, the production of these galls do not seriously injure the plant and are only an aesthetic issue, but be sure to keep an eye out for any reduced vigor associated with these galls.

Plant galls take many different shapes, sizes, and forms! Often, an insect will lay her egg on/in a leaf, and the feeding young larva will cause the gall to form around it, providing necessary nutrients and protection from predators. Some insects only lay one egg on a leaf. This was obviously not the case in the above photo. Photo credit: Nick Goltz

…and (Nearly) Everyone Else

It’s important to remember that most of the insects we encounter in the garden are harmless or beneficial – pollinating our plants, eating pests and keeping the insect community diverse and healthy. Be sure to only apply insecticides as a last resort and only when pollinators and other beneficial critters aren’t present. The best time of day to apply insecticides (to minimize sun injury and contact with pollinators) is in the evening when plants are dry unless otherwise specified on your product label. Not sure what insect is visiting your garden? Contact the folks at the UConn Home & Garden Education Center by emailing ladybug@uconn.edu for advice and identification services.

Nick Goltz, DPM

The past two years have been very challenging years for gardeners. I find myself wishing for a “typical” year as we seem to have swung from one extreme to the other. Last year was a complete wash out, with many crops not coping well with the seemingly constant rain. This year we go to the complete opposite – dry! I cannot believe how fast my crops are literally wilting after I water them. I got taken by surprise by the extremely hot weather a few times, and while spending too much time at work, ended up missing a few waterings. It seems there is little forgiveness for this. How many times I uttered the phrase “but it was supposed to rain” as I looked at struggling plants. A lot of how well your crops will cope with weather extremes depends upon your soil type. Heavy clay soils tend to hold on to moisture; in wet years this can lead to a lot of fungal diseases. Sandy soils dry quickly, so in years of little rain it can be difficult to provide enough water. If you have a nice loam soil, then you have the equivalent of Goldilocks’s porridge that was “just right.”

This winter squash and corn patch benefits from afternoon shade. Note the wilting plants in the front left of the photo, and the bone-dry grass in the foreground. Photo by mrl2022.

I wrote an article a year ago where I commented about how well some varieties of green beans coped with the wet weather. It is interesting (making the best of it) to see how those same varieties of beans coped with the dry conditions. Although not a formal scientific study, the observations of these plants are notable. I generally plant three varieties of bush green beans: green, yellow, and purple. These are the same specific varieties I plant each year. During the wet year, the green were the first to die off, followed by the yellow.  The purple seemed to tolerate the wet weather quite well and produced a huge crop. Now that we have a dry year, the opposite seems to be holding true. The purple was the first to die off, the yellow are struggling some, but the green seem to be thriving. In a “normal” year, I have all three varieties producing a large crop. It is only in times of extremes do the tolerances become important. Most farmers choose varieties of crops that are well suited to their particular set of growing variables (soil, sun, soil chemistry, cultural habits, etc.). Interestingly, I have one variety of pole green beans that seemed to thrive in both the wet and the dry years. 

These family heirloom pole beans seem to thrive in all types of weather. No wonder they have been in cultivation for hundreds of years! Photo by mrl2022.

Watering sounds easy, but it can lead to trouble. Frequent irrigation with no rain can, over time, lead to salt accumulation in the soil. This is because when water evaporates, the salts dissolved within can stay behind. We usually do not see this here in the northeast, but the southwestern United States can. Due to time limitations we all suffer from, it is tempting to water a short sprinkle frequently, but this is not good for your plants as it encourages shallow roots. It is better to water less frequently, but for a longer period of time to encourage deep roots. Deep roots help the plant survive during times of drought. Having said all that, I have never seen the soil so dry as I did this year. I water with a sprinkler, and this year I had to increase my watering duration by 50 percent to adequately wet the soil. If your garden is small enough, it is a good idea to use drip irrigation. It wastes less water by putting it right by the plants. This requires running plastic piping throughout your garden, periodically poking a hole in it, and running a drip line to each plant. It is somewhat tricky to then rotate your crops the following year as the plumbing will generally need a different configuration. Careful planning may allow for some flexibility in this situation. Drip irrigation has the added benefit of not wetting the leaves, which can cause burn spots in some plants, and contribute to diseases in others. A less expensive alternative is a soaker hose which just seeps water along its entire length. This is simply snaked through the plants.  Remember though that watering is expensive! If you are on city water, you will have a substantial increase in your bill, and if on a well water, higher electricity costs. This assumes your well has enough water to keep up with the increased demand. The bigger the garden, the more water needed.

The last thing I wanted to comment on was shade. Although I generally think of shade as an enemy of agricultural crops, it can certainly work to your advantage in certain situations. This year, afternoon shade has helped keep some crops from drying out. My winter squash and corn seem to be thriving with some afternoon shade (this is the hottest time of the day!). The plants in my kitchen garden do not seem to wilt if in the shade of a poorly placed mulberry trees (I did not plant it so close to the garden; it was there when I purchased the house). Many times, gardeners will use shade cloth to cool heat-sensitive crops like lettuce. Shade may decrease the temperature by ten degrees. This can help the lettuce resist bolting. Don’t forget to select varieties resistant to bolting as well. Be careful of shade though. Hot, wet, and shady can lead to powdery mildew in a number of our favorite ornamental and food plants (phlox and zucchini for example). Most of our agricultural plants need six hours or more of sun each day.

This variety of cucumber thrived in last year’s constant rain, but struggles to hang on during our current dry weather. Photo by mrl2022.

The thing to keep in mind is that these extremes do not usually happen. You may get a few years in a row like we have had, but there are many more typical years to come. Use these years to your advantage and learn what you can. Try not to let yourself get frustrated. I find myself thinking about my soil composition more now than ever. This would be a great time to get your soil tested. Adding compost can help aerate clay soils, and hold moisture in sandy soils.  Compost not only adds nutrients to the soil, but also improves nutrient retention. I like making observations and comparisons in these types of years. For example, in last year’s wet, the cucumbers grew like crazy. In this year’s dry, they have not grown much at all. Apparently, cucumbers like a lot of water (but not soggy soil which leads to disease). Experiencing and now knowing this can help me grow better cucumbers in years to come. So many people rate their garden as successful or not by the amount of produce produced in a given year. Of course, each year this is the goal, but when you learn more about your soil and plants this can help you grow more crops during your entire lifetime. To me, the knowledge is the most valuable part!

Matt Lisy