About kathyedoisy

I'm a retired MU entomologist and stream ecologist. I've been an avid gardener for over 40 years and love to cook and preserve what we grow in our garden.

It’s Sweet Potato Time!

Have you ever noticed that as you grow older you start to like foods that you thought you didn’t like at all? I sure have! One vegetable that I really didn’t like in my youth has gradually become a favorite of mine. What vegetable is it? Sweet potato! 

cluster of sweet potatoes just pulled out of the ground

Sweet potatoes are related to the morning glory vine, and if you see some flowers on yours late in the season you will recognize the similarity. They are only distantly related to common potatoes and not at all related to true “yams.” They are believed to have originated in central or southern America and Columbus appears to have been the first to bring them to Europe (Wikipedia). By the time European colonists came to what is now the U.S., sweet potatoes were already a part of their gardening plans. 

The reason I started growing them was curiousity. I had a little extra garden space, and my neighbor had some extra “slips.” Sweet potato slips are the rooted shoots from the tubers that are used to start a new crop. The CGC offers slips to gardeners during the warm season plant distribution each spring. I did some quick reading on how to plant them and stuck them in. A nice mounded trough full of sandy compost is ideal. No need for any chemicals in Mid-Missouri, plus they like hot, dry weather! By late summer, the vines had attempted to cover everything in and around the garden, including my husband’s truck! But any hassle they caused they made up for at harvest. From year to year my production has varied, but I have harvested as much as 160 pounds of tubers from four slips! Imagine getting that kind of production when there’s no grocery store to tide you through the winter. No wonder this crop has spread all over the world!

The author holding up a 12-pound sweet potato in front of her face.
Author with her personal record 12 pound sweet potato.

There is a trick to storing all that bounty. Sweet potatoes must be “cured” before storing. Curing not only improves storage (I still have one ready to eat from 2018), but also makes them sweeter and higher in nutrients. If you doubt this, try eating one straight out of the garden, make a mental note of how sweet it is, and then compare that to a cured potato one month later. In commercial production, tubers are stored in large buildings at 85-90 degrees (F) and about 90% humidity for anywhere from 5 days to 2 weeks. Unfortunately, that’s not so easy to replicate around here in the fall. 

Here’s what I do. For one thing, NEVER let frost touch your vines. Sweet potatoes are a tropical plant, and frost encourages them to quickly rot. Starting in late September, I keep a close eye on the weather forecast. What I’m watching for is a late hot spell. A day or two before it hits, we cut off all the vines (the leaves can be eaten). Then when it’s at least 80 degrees, we dig them up and let them sit all day in the shade of other garden plants. Next we gently knock off the dirt (do not wash them), and either place them in a shaded hot place outside or, if necessary, move them into the hottest room of our house, making sure they are shaded. I doubt I have ever met the humidity requirements, but like I said I still have an 11-month old sweet potato to eat, so I must be doing something right. When I feel like they’ve cured long enough, I move them down into the basement. Cured tubers keep best at about 60 degrees in the dark. 

So, what’s the best way to eat a sweet potato? For me, baked and then mashed with butter, brown sugar and fresh grated ginger — I actually converted a previous sweet potato hater with that fresh ginger addition. They are also good diced and roasted with a little olive oil and salt, or made into sweet potato fries. My neighbor who started me down this road makes them into black bean and diced sweet potato quesadillas for the kids at her daycare. Apparently they love them! And since sweet potatoes are chock full of beta carotene and vitamin A, nutrients that are lacking in many American’s diets, why not give them a try? 

For additional information on growing sweet potatoes here are some handy links:

When to Plant Your Warm Season Vegetables

When should you plant your warm season vegetables?

This weekend, May 11 and 12, the Community Garden Coalition will offer warm season plants like tomatoes and peppers to gardeners. See times and other details.

So, we thought we’d take a moment to explain why we chose a date in mid-May despite some long periods of warm weather in April.

Weather in Mid-Missouri is highly variable, as anyone who has lived here for more than a month knows! When gardening experts discuss freeze dates for our area there are two critical time periods. The first is the average frost-free date. The second is the final frost-free date.

Although these dates shift over time, a recent report by Pat Guinan the state climatologist lists April 10 as the average frost-free date for Boone County. However, local factors can impact this. For instance, valleys tend to be cooler than hilltops, and urban gardens are usually warmer than rural ones because all the concrete holds the temperature higher.

The latest frost on record in Columbia was May 9, 1906. That may seem like a long time ago, but we were close to freezing this year on April 27. We want to give our gardeners, especially eager new ones, the best chance for success. Distributing sensitive plants a little later can avoid the sad circumstance of a late frost killing everything.

garden plants protected wih buckets and sheetsHere’s what my vegetable garden looked like in preparation for the cool weather at the end of April. As an experienced gardener, I am a gambler and my heirloom tomatoes were getting too big for my indoor pots. As you can see, protecting those transplants from frost was a lot of work, and not many gardeners are up to that sort of challenge—material and time wise.

Another consideration is that many warm season plants, especially eggplant and peppers, don’t like “cold feet.” They want warm soil to send their roots into, and can become stunted and drop their flowers when temperatures dip below 50 degrees.

It’s always a guessing game to pick the optimum time to plant in mid-Missouri, but these are some of the factors we try to balance when we plan our events. Hopefully the warmer weather will hold for the rest of May and your garden will grow happily.

The Boone County Buzz: How to Foil Flea Beetles

Does it look like a tiny shotgun has blasted the leaves of your eggplant? (See Figure 1 for an example.) Chances are you have a flea beetle infestation. First of all, don’t worry, “flea” beetles only bite plants! These are not like the fleas on your dog or cat. That’s a whole different order of insects. These are very small (1/10 inch) leaf-feeding beetles that are called “flea” beetles due to their large hind legs which enable them to jump much like fleas (Figure 2).

Eggplant with flea beetle damage.

Figure 1. Eggplant with flea beetle damage. Photo, Ali Eminov [CC BY-NC-ND 2.0]

Adult flea beetle

Figure 2. Adult flea beetle

There are several species found in Missouri but the only species I see regularly is all black. Depending on the species, they may feed on cruciferous vegetables, spinach, turnips, radishes, tomatoes, potatoes, peppers, beans or eggplant. The good news is that the adults die off in July. The bad news is, they can have two generations per year, meaning they can come back for your fall crops. Generally speaking I ignore flea beetles and their damage except when it comes to young seedlings. (Mature plants can usually sustain a bit of flea beetle damage to leaves and still provide fruit.)

For years, flea beetles have severely damaged my eggplant transplants. If I’m lucky, a couple plants survive, and, by late summer, I finally have plants that are large enough to produce. I have tried row covers to no avail. The problem here is that the adults overwinter in your soil and leaf litter. Despite clearing the plant debris from my garden in the fall there are still plenty of hungry adult flea beetles just waiting in the soil for some tender eggplant leaves.

Last year I tried an experiment. Since I only grow four eggplant every year, I went out and purchased some hard plastic domed frost guards. Eggplant are notoriously cold sensitive, so why not? In addition, I thought they might act as a physical barrier to hungry flea beetles. I figured if I found any beetles under the dome, I would shoo them off and quickly replace it since flea beetles jump when startled. In practice, I never needed to do this as the domes worked quite well. After a week I checked and the transplants were hole-free. To test my experiment, I uncovered one of my eggplants. Three days later, when I went out to compare it to the still-covered plants, I found that the unprotected plant was COVERED with flea beetles and feeding holes. The domes worked!

FRGD Frost Guards from Gardener’s Edge

Then, in an effort to save my sacrificial eggplant, I tried spraying it with organic neem oil. WOW! Another real find! It took several sprays, but apparently the flea beetles think it tastes as bad as it smells! They either died or left. My eggplant grew up, became highly productive, and I ended up with a freezer full of tasty ratatouille which my sweet husband enjoys.*

While I think I’ve cracked the code on safe ways to control flea beetles, there are some good suggestions on the websites listed below for other earth-friendly ways to lessen flea beetle damage:

* I have the BEST recipe for ratatouille. Email me at kathy@comogardens.org if you’d like it.

The Boone County Buzz: Are you a gambler?

I am! No, you won’t ever find me at the casino. I’m talking about gardening! I think most of us who garden have a touch of the gambler in us. How else can you explain the leap of faith we take every year when we put our seeds or baby transplants out in the wild world dreaming of luscious produce to come? Sometimes things go well and some not so well. That’s just part of life.

Well, today I want to encourage the wildest gamblers out there to take a chance on REALLY early spring lettuce. You know how all the seed packages say to plant your lettuce from mid-March to mid-May? I think they’re missing the boat!

mixed baby lettuceI followed those recommendations for years and what always happened was that as my lettuce finally started to head up it became bitter! The bitterness used to start around mid-June but I’ve had it happen as early as mid-May when temperatures are unusually warm. As a crazed, baby lettuce aficionado this is most frustrating.

Then about 15 years ago I was reading some book (?) where an old woman from the Ozarks said to put your lettuce seed out as soon as the snow melted. This seemed like insanity, but, again, I’ve got a gambling streak. I tried it. Yes, I ran out with a cloth sheet to protect it a few times. But I was eating beautiful baby lettuce salads by the end of March! Needless to say, I’ve been doing this ever since.

When exactly do I take this risk? It varies with the weather and snow. Looking back in my garden diary (yes, you really should keep one) the first planting has been as early as January 5th but probably averages around January 25th. Have I lost my lettuce? Maybe once, but most varieties of lettuce can survive temperatures as low as 20 degrees Fahrenheit. Since lettuce seed is somewhat viable for up to 6 years I usually use old seed from a previous year, so if it is lost I won’t feel quite as bad. Sometimes, when the cravings are severe I’ve been known to start lettuce seeds inside in January and plunk the plants out in early February. Again, it’s a gamble but what an incredible payoff if you succeed! Take a chance!

Boone County Buzz: Our Insect Hotel Has Tenants! YAY!

Kathy Doisy

Kathy Doisy

In case anyone is wondering if our insect hotel is working, I have proof! If you look at the bamboo on the lower right, you can see that several of the holes have been covered with green pieces of leaves (Fig.1). This is the work of leaf-cutter bees (Fig.2). In July, a friend found me a mini-insect hotel that was going for cheap at Aldi’s — you know something is getting trendy when Aldi’s starts selling it. Anyway, while it didn’t have quite the flair of the one my beloved made for me, I thought why not? Well as you can see several of the holes have been sealed with mud by mason bees (Figs. 3 and 4).

Bamboo tubes filled with cut pieces of leaf.

Figure 1. Brood chambers of leaf-cutter bees.

Mason bees and leaf-cutter bees are represented by several species in the family Megachilidae. Most of the bees in this family are solitary bees meaning that each female performs all her own tasks, unlike the division of labor in a honey bee colony. She collects pollen on fine hairs on the underneath of her abdomen (this pollen spreads easily to the next flower making them excellent pollinators), then finds an appropriate tube to lay an egg in, while provisioning it with pollen for when her hungry larva hatches.

Picture of small bee on flower

Figure 2. Common species of leaf-cutter bee (USDA ARS free image).

She then seals that part of the tube with either a piece of leaf or mud, depending on the species, and goes looking for more pollen to repeat the process until all the space in that tube is filled. Whew, sounds exhausting! Which is why these small, gentle bees don’t waste their time defending their brood like honey bees. The only way you’ll get stung by one of these is if you grab it.

Image of bamboo tubes sealed with mud that looks like masonry.

Figure 3. Brood chambers of Mason bees.

Now here’s where it gets really interesting — at least to me. I went out to look at our homemade insect hotel and found that a new, different species has recently been using some of the tubes and stuffing the openings with grass (Fig. 5). I did a little research and found out there are several species of “grass-carrying” wasps in the family Sphecidae that also use these tubes for their brood. These wasps aren’t as good at pollinating as our solitary bees, but I’m a big fan of diversity and isn’t that grass cute? I’m hoping to catch one in the act.

Picture of small dark bee on flower.

Figure 4. Species of Mason bee (USDA ARS free image).

Picture of bamboo tubes with long pieces of grass sticking out the ends.

Figure 5. Brood chambers for “grass-carrying” wasps.

I think the take home point of this whole endeavor is highlighted by the fact that we live just a couple of blocks from the massive Brookside student apartment complex. Can sweet little pollinators thrive so close to all that concrete and trash? Apparently, yes. You can live downtown and still help nature. In fact, recent research indicates higher abundance and diversity of native bees in urban areas where there are higher densities of flowers and less pesticide use than fields in rural areas (D.M. Hall, et al. 2017. The City as a Refuge for Insect Pollinators. Conservation Biology 31:24-29.)

So, no more excuses! Start doing your part! Why not put a few native plants along the border of your veggie garden? If you don’t want a perennial, then plant a few annual sunflowers or zinnias. Both are good nectar sources for many insects and make lovely bouquets. For more information on helping these pollinators while producing nourishing food for yourself and friends, take a look at this website:

The Honeybee Conservancy

Boone County Buzz: We Love Squash (So Do Bugs)

round zucchini growingWhen I hear stories of gardeners abandoning cucurbits (AKA zucchini and other squash) on people’s doorsteps, I wish this was my problem. Why do I have trouble growing these plants? I don’t use pesticides. If you want to kill some bees and reduce your yield, treat your zucchini plants with an insecticide.

Kathy Doisy

Kathy Doisy

My first job at MU was on an EPA program called “Rebuttable Presumption Against Registration.” Our job was to send the EPA data on the pros and cons of using various pesticides. Essentially asking whether the risk was worth the benefit. Based on that experience, when it comes to flea and tick control I’m on-board with man-made chemicals. (I apologize to my Kitty Boys but there is nothing worse than a home flea infestation). However, putting chemicals on something I’m eventually going to eat just doesn’t happen unless it’s absolutely, positively necessary. That means that to harvest a lot of squash and other cucurbits I have to do some serious plant monitoring. My methods are working pretty well, as we have gone from losing our plants to insect pests by the first of July, to harvests still going on in September (knock on wood)! My freezer is filled every year with my version of a delicious summer squash bisque! (If you want the recipe email me!)

adult squash bug

Figure 1. Squash bug approximately ½ to ¾ inch long. Photo, Keith Weller, USDA.

When it comes to growing squash or cucumbers around here, the big problems are squash bugs, squash borers and cucumber beetles. Anyone who has ever grown squash two years in a row knows what a squash bug looks like (Figure 1). The squash borer adult is more elusive (Figure 2). Our cucumber beetles tend to be the twelve-spotted variety (Figure 4).

adult squash vine borer, photo by Jesse Christopherson

Figure 2. Squash borer approximately ½ to ¾ inch long. Photo, Jesse Christopherson

Here’s what is working for me with the squash bugs and borers.

First, I clean up my garden waste after the first hard freeze in the fall. This way I’m removing overwintering sites for many pests including the squash bugs. Then in the spring, I plant two separate patches with summer squash as far apart as possible and leave 4 or 5 plants per mound. Depending on your garden size I recommend planting your cucumbers and winter squash in the same fashion. It may be crowded at first but it is inevitable in gardens over a year old that one of these pests will kill some of your plants.

Most mornings I get up early (it’s really nice out then — it’s cool, the birds are singing), I put on my flexible garden gloves, take my 5-gallon bucket of soapy water and an aerial (butterfly) net to the garden. First I sneak up on my plants looking for adult squash borers laying eggs near the base of my plants. It’s their larvae in the plant stems that make your otherwise healthy zucchini plant suddenly collapse and die. If you see one you have to act FAST. I swoop the net on top of it and then hold up the end of the net so they will fly up into it. Catching them on the wing is more difficult, but when you succeed it’s thrilling (well at least for a 62 year-old woman).

Squash bug eggs and immature squash bugs. Photo, Zsofia Szendrei,

Figure 3. Squash bug eggs and immature squash bugs. Photo, Zsofia Szendrei, Michigan State University

Then, when I’m done scouting for those I start looking for adult and immature squash bugs, but more importantly squash bug eggs (Figure 3). These are usually laid in clusters anywhere on the plant. When I see the eggs or immature bugs on a plant leaf or stem I remove part or all of that leaf and plunge it under the water in my bucket. If I see an adult or near-adult bug I crush it with my gloved hand or step on it. I’ve killed thousands and never been hurt, so don’t be afraid to do it.

spotted cucumber beetle

Figure 4. Spotted cucumber beetle approximately 1/3 inch long. Photo, DrPhotoMoto

Unfortunately I don’t have much luck removing cucumber beetles by hand. The damage they do to my cucumbers by feeding is negligible, but they do a lot of damage by transmitting a bacterial wilt, which is why I plant several vines on each patch. Usually one of them makes it! For other ideas on how to deal with these pests, take a look at the websites below.

Missouri Botanical Garden – Cucumber beetles

Missouri Botanical Garden – Squash borers

Missouri Botanical Garden – Squash bugs

The Boone County Buzz: Bugs in Your Broccoli?

Kathy Doisy

Kathy Doisy

“Cruciferous” vegetables include cabbage, broccoli, kale, cauliflower, arugula, and the list goes on. These crops love cooler weather and are known as “super” foods, because they are packed with nutrition. I don’t grow large quantities of them. It’s not that we don’t like them, but from past experience it seems like all the “heading” types become ready to harvest almost simultaneously. If you don’t have a big family or like to do serious fermenting, pickling and/or canning, it may cause more stress than pleasure. So, if you do like broccoli, cabbage or cauliflower, but have never grown them, I have a suggestion. On March 24th and 25th, the CGC will be offering transplants of these cool season vegetables at the Claudell garden. Why not ask for a couple of each? That way you can see how it goes without being forced to get 4-6 of them at the nursery or big box store. Also, please remember when picking up these plants that a donation helps us keep all of this going!

cabbage white butterflies

cabbage white butterflies (photo Masaki Ikeda)

Another reason for the scarcity of these types of veggies in my garden is the large number of insect pests that LOVE cruciferous plants. I don’t like to use chemicals, especially on the parts of a plant I’m going to eat. This means that for each cruciferous vegetable that I do grow I spend a lot of time monitoring it for pests.

When I walk out for my daily garden inspection I’m always wearing lightweight, flexible gardening gloves and carrying a bucket of soapy water. This allows me to crush or drown every garden pest I encounter. (Though bunnies and turtles get a pass.) For someone who has pet spiders in her home, I can be surprisingly vicious when it comes to biological control on my plants. Another possibility is row covers which will at least slow down the flying pests. Our long-time board member Bill McKelvey says that he grew spectacular cauliflower and broccoli last year using row cover, so I’m going to give it a try. The materials for row covers will be available along with seeds and the transplants at the Claudell Garden on the aforementioned dates.

garden beds demonstrating use of row cover with hoops, photo by Mark The Trigeek

Using row cover and hoops over a garden bed. (Photo by Mark the Trigeek.)

Unfortunately, I can think of twelve different species that can wreak havoc on various cruciferous vegetables. I don’t have the time, space or inclination to address all of these potential pests and chemical-free ways to grow them, but fortunately I don’t need to. Below you will find several links where someone has already done it for me.

Identification of cruciferous insect pests:

Earth friendly suggestions for control of some of these pests

(Tip: These sites all offer recommendations on other pests, too.)