Growing squash – problems and solutions

Squash plants love the hot summer sun, and Kansas has plenty of it! Any vegetable gardener in the state who has been growing for very long will likely have planted some variety of squash. There are a few issues that can pop up when growing squash, but overall, it is usually pretty easy to grow.

In the Demo garden, we are growing both summer squash and winter squash. Contrary to what the names imply, both types of squash are grown during the heat of summer; one main difference is that summer squash is grown for its young or immature fruit (think zucchini), while winter squash is grown for its fully mature fruit, so it takes longer to be ready (think butternut squash or pumpkins).

Summer squash grows in a bushy shape and is generally ready to harvest by mid-summer. When harvested at small sizes, they have a soft, thin skin and unsubstantial seeds and can be eaten raw. If left on the plant to grow very large, though, they become tough and too bitter to eat raw. The most popular types of summer squash are zucchini and yellow squash, but other types include pattypan and tromboncino.

We have two varieties of summer squash in the demo garden, and both are varieties of zucchini: ‘49er’ and ‘Astia,’ which both are beginning to yield a harvest.

‘49er’ is a yellow zucchini which has about 50 days to maturity (DTM), and ‘Astia’ is a dark green zucchini with 48 DTM. Both are best harvested at about 5-6 inches long. (Yellow squash and yellow varieties of zucchini are similar, but different; zucchini maintains a relatively consistent diameter, whereas yellow squash is broader at one end and tapers toward the other, and often has a slightly thicker skin than zucchini.)

’49er’ zucchini
‘Astia’ zucchini

Winter squash generally has a vining nature and needs either lots of space to sprawl out or a trellis to grow vertically when space is at a premium. Because it is harvested when fully mature, it has a tougher skin than summer squash that is not usually eaten. Winter squash is usually ready to harvest late summer or early fall. One of the benefits of growing winter squash is that it can store well, even through the winter months. The winter squash in the demo garden (‘Waltham’ butternut and ‘Autumn Frost’ acorn squash varieties) are setting fruit but won’t be ready to harvest for several more weeks. We’ll keep you posted!

Winter squash has reached the top of the trellis!
‘Waltham’ butternut setting fruit

A couple of the biggest challenges with growing squash are the squash vine borer and the squash bug.  Both of these insects can wreak significant havoc and are taking their toll now in the Demo garden.

The classic symptom of squash vine borer is a wilted plant when the plant has been watered well and shouldn’t be drooping. Upon closer inspection, you may be able to see that the stem has small holes or is chewed up close to the ground with larvae frass at the base. At this point, it is important to remove the larvae by either disposing of the plant completely, or, if you’re feeling surgical, slitting the vine with a sharp knife until you find the larvae and then removing it. The slit vine can be placed back in the soil and kept moist in the hopes that it will send off new roots, but some plants may have been damaged beyond repair and won’t recover from the “surgery.” If the larvae are not removed and are allowed to complete their life cycles in your garden (in which they eat their way out of the stem, burrow 1-2 inches into the soil, and wait in a cocoon until the next season), the problem will likely return next year. Once you have squash vine borers, there is not a whole lot you can do; to learn about treatment options and cultural controls, see this helpful publication.

Vine borer holes in plant stem
Vine borer larvae found in a plant stem

Another pest we are facing in the Demo garden is squash bugs. Adults look similar to stink bugs and can be found on many species of the cucurbit family, but squash is their favorite. Adults and nymphs (which are lighter grey with black legs) cause damage by sucking out juices from plant leaves, resulting in yellowing, wilting, and death of the plant when populations are large. Squash bug eggs can be found by scouting on the under sides of leaves – they are glossy brown and laid in groups in between leaf veins. These eggs can be scraped off and disposed of to help control, but here in the Demo garden, the problem has passed the egg stage, and we have begun chemical control to limit the damage. Squash bugs are best controlled at the nymph stage, since adults have a hard shell that protects them from pesticides. We have applied one round of spinosad by spraying it on the vine and branches where the nymphs are congregating. We won’t be able to harvest zucchini for at least three days after spraying, and depending on what the squash bug population looks like after the application, we may spray again in about a week. We use chemicals sparingly in the Demo garden, which are safe when used appropriately. As always… when using chemical pesticides, make sure read and follow the label! To learn more about squash bugs, click here.

Squash bug adult and eggs
Squash bug nymphs

One last issue we had with the zucchini earlier this year was small fruit (around 3 inches) that shriveled up or rotted from the blossom end of the fruit before coming to harvestable size. This symptom can be due to a couple of different culprits, but is ultimately related to an issue with pollination.

Sometimes high temperatures following a mild or cool spell can limit the number of pollinators that are active in the garden; sometimes over-fertilization (high nitrogen levels) in the soil can cause the plant to produce too many male flowers; and sometimes plants don’t produce enough male and female flowers at the same time to ensure enough pollination (this issue usually resolves itself as the season progresses.)

We stepped in to lend our zucchini plants a pollinating hand, and you can too if you see this issue in your garden – it is as simple as taking the pollen from the male flowers and transferring it to the female flowers. First, identify which flowers are female and which are male; female flowers often have a swelling behind the flower head where the fruit is barely beginning to form, whereas male flowers have a straight stem behind the flower head. Another, perhaps more reliable way to tell is to look inside the flower: the female has a stigma which is larger and slightly round or bulbous, and the male has a single, straight appendage – the anther – inside the flower.

Hand-pollinating can easily be done by using a small artist-sized paint brush to transfer pollen from the male to the female flowers; lightly touch the tip of the brush to the anther on a male flower and dab the pollen that the brush picked up onto the stigma of a female flower.

With a couple hand-pollinating sessions, a relative evening-out of temperature, and an uptick in pollinators in the garden, our zucchini are now producing harvestable fruit. Now it’s a matter of fending off the squash bugs so that we can keep harvesting this delicious summer garden staple!

Resources for further reading:

Squash bugs

Squash vine borers

Pollination problems

By: Maureen Wilbeck, Master Gardener

Beans: from garden to plate

Beans are a Kansas favorite in the vegetable garden. These warm-season plants are well acclimated to our tough Kansas summers. Once planted, they grow very fast and most varieties are ready to harvest in seven to eight weeks.

In the Demo Garden, beans are starting to produce. It is best to harvest when the pods are firm and crisp, but the bean seeds are not yet bulging. If at all possible, don’t pick them in the early morning when there is dew on the plants, as blight, a common bacterial disease, can easily be spread from one plant to another via splashing water droplets. So, make sure the plant foliage is dry before harvesting. 

Green beans are typically grown for their immature pods. Beans such as navy and lima beans are allowed to fully ripen and then the bean seeds are removed from the pods; these types of beans are harvested much later in the season.

A bean that’s ready to harvest

On April 28th, we planted four different varieties of bush style green beans (also called snap beans) in the Demo Garden: Heavy Harvest, Tenderette, Royal Burgundy, and Tendergreen Improved.

‘Heavy Harvest’ is a 53-day bean. This medium green-colored bean is also slender and grows about five inches long. So far, it is not living up to its namesake in that it has only yielded a small amount of beans so far.

‘Tenderette’ is a 58-day variety of bean. It also grows about five inches long and is slender. It is medium green in color. As with Heavy Harvest, this too only had a few ready to be picked.

‘Royal Burgundy’ is a 55-day variety that generally grows about five inches long. It is a slender bean with a deep purple coloring that is very beautiful and makes it very easy to see against the green foliage. Again, there were only a handful of beans to be found, but we are hopeful that with a little more time, they will start producing more.

‘Tendergreen Improved’ is a 52-day variety. The coloring, although still green, had a bit of a lighter, yellowish undertone compared to the other green beans. These beans are a little longer, growing up to six inches in length and is also plumper than the other varieties. The thing that is most impressive about Tendergreen so far is the yield. While it makes sense that there are more harvestable beans of this variety right now because its “days to maturity” (DTM) is shorter, this variety is still likely to out-produce the other varieties – but we will keep you updated!

So how do they cook up?  Using a quick, identical technique on each variety, we tested them “tender-crisp” style. After the ends were trimmed, a ¼ cup water was added to a skillet along with the beans and cooked covered for three minutes. Then the cover was removed to allow the water to fully evaporate. A touch of butter was then added to each. 

My personal favorite is the Tendergreen Improved. It was the most tender of the four varieties tested as well as the most prolific producer. Tenderette and Heavy Harvest where just slightly tougher than Tendergreen. Although the most unique to look at, the Royal Burgundy was the toughest of all the varieties, but interestingly, it turns from purple to green when cooked.

One final note: there was some significant stippling on the leaves of the beans, which is an indicator of spider mites. Spider mites are tiny, barely visible spider-relatives that suck juice from the underside of leaves and are common during hot, dry weather.

Stippling on bean leaves

As a first defense against this garden pest, after harvesting the beans, we used the garden hose with a jet spray setting and shot the underside of the leaves with as much coverage as possible, and we plan to repeat this process a few times a week. Hopefully these pesky critters won’t ruin the harvest!

Spraying spider mites off of under side of bean leaves

Click here to learn more about growing beans or spider mites.

By: Maureen Wilbeck, Master Gardener

Purple Sprouting Broccoli

Broccoli is one of those vegetables that can be a little bit “hit or miss” in Kansas, especially in the spring. The cool parts of the growing season, spring and fall both, can sometimes be too short and too erratic to have great broccoli. Over the years we have tried several kinds of broccoli, some that performed well and others not so much.

This year, we chose to plant ‘Burgundy,’ a variety of purple sprouting broccoli. Sprouting broccoli is selected for high quality, uniform, and prolific side shoots. Many older “heading type” broccoli varieties would produce some side shoots, newer varieties not as much. Sprouting broccoli is designed to have the center “head” shoot pinched out at a small size to encourage more side shoots.

49948988198_0540ccf06fWe started these plants from seed in mid-February and transplanted them into the garden on March 17th. They are supposed to take about 37 days from transplant to maturity…but the weather was definitely not helpful on that front this year. About a week ago, the plants were showing the development of the center shoot. (About 60 days after transplanting – thanks, cold snaps!)

49949488156_135742dc9aI snipped out the center stalk, and you can already see the side shoots starting to grow.

49949016143_170feb2b8bThis is what the shoots are looking like now. I love the purple color! So often with purple vegetables, the color is disappointing, but this is beautiful. It is important to note that the color will fade to a beautiful dark green once it is cooked.

From a flavor standpoint, this broccoli is strong. The little bit that I have nibbled on, it has a very strong mustard flavor. Most homegrown broccoli is that way, and once it is cooked, it has great flavor – but it is not the mild and water flavor you maybe have come to expect from even fresh grocery store broccoli.

The idea with the side shoots is that they should continue to develop and be produced until it gets too hot, potentially having a higher yield for a single plant than with a heading type.

If you wanted to give this plant a try (and you can find the seeds available!), you should start the seeds indoors in mid- to late June, then transplant outside in late July. With some luck and decent weather, you should have some awesome broccoli sometime in September!

2020 Tomato Trials

Our tomato trials are looking very fortuitous at this point in the year. When we were planning this winter, we chose to try out some of the more recent All-America Selections tomato winners. These are varieties that have been tested all across the U.S. and have shown to perform reliably under a wide range of conditions.

We had already grown Chef’s Choice Orange a couple of times and found it to be a reliable producer with great flavor. (I have also grown it at home for a few more years and it has quickly become one that is an easy choice.) Chef's Choice Orange tomato

With that experience, we are interested to see if other, new varieties in the Chef’s Choice line will be just a promising for Kansas. We chose to grow the Chef’s Choice Orange again as our “known” trial variety. To that, we have added the following varieties. (Links to the All-America Selections pages, with more variety details.)

Chef’s Choice Red – 8 oz fruit, prolific

Chef’s Choice Green – Green and yellow at maturity and citrus-y flavor common to green-when-ripe tomatoes.

Chef’s Choice Yellow – 10 oz. somewhat sweet fruit

Chef’s Choice Pink – 12-14 oz beefsteak with pink skin and flesh

We also chose two non-Chef’s Choice varieties to test in order to have a broader comparison.

Galahad – Red fruit with high disease resistance and purported crack resistance. (Crack resistance is a hot commodity in Kansas, so we are hoping for great things!)

Mountain Rouge – From the “Mountain” series, a 12-14 oz. pink beefsteak with high disease resistance.

Some Cherry Tomatoes:

In other areas of the garden, we also have some cherry tomatoes planted, and these are a little further outside the normal varieties.

Moonbeam – A pale yellow or white grape tomato that is supposed to have high yields and exceptional flavor.

Brad’s Atomic Grape – This multi-colored tomato has been all over social media for a couple years, but we have heard from some locals that it cracks horribly. So…we’re going to give it a try!

Blush – A yellow oblong cherry with red stripes and interior blush. We have tried others in this series in the past, all with bad cracking problems, so it will be interesting to see how this one performs.

If all goes well, we hope to have a bounty of tomatoes this year, as well as some great new varieties to recommend in our area.

Updated Garden Plans!

49813022538_4a9e22a359It has been quite the ride since I posted our first look at garden plans for this year, hasn’t it? So many things have changed, and likely many others will before it is all said and done. Because our face-to-face programming is suspended for the time being, we have been thinking about how to adjust our garden for the summer to accommodate the safety of our staff, volunteers, and the public. At the same time, we know that many new gardeners are seeking information on how to start and maintain a successful vegetable garden, and that access to fresh, healthy food is more important now than ever. (And it has always been important!)

Because most of our early spring planting was eliminated, with the exception of plants that we already had ready to go, we have re-planned chunks of the garden to change those plans. We also had several parts of the garden that were planned to be more novelties, ornamental, or trials of things that we didn’t know quite how they were going to perform. In order to best fulfill our educational mission and serve our broader community, we have eliminated the majority of those types of plantings from the garden, and will instead replace them with the following:

  • Extra tomato and pepper plants that we had started already.
  • Beans, squash, and other common, generally productive vegetables that we had available.
  • Additional plantings of varieties we have grown in the past, had leftover seed in stock, and knew were going to be productive to replace trial varieties that were less likely to perform well.

Some of the things that we have maintained include:

  • Planting the square beds (8, 9, and 10) to perennial fruit plants. If you look at the pic above, you can see the dwarf apple in the front and the blackberries and raspberries growing in bed 9.
  • Vertical gardening / trellises to grow lots of cucumbers, melons, and other things throughout the garden.
  • The tomato trials of recent All America Selections winners.
  • Lots of different colors of veggies!

An additional change, along with planting varieties that emphasize productivity, is that we will be donating significantly more of the produce to those in need. Most years, a large portion of our produce is used for educational programming – for our Master Gardeners or others in the community, and extra produce has been donated. This year the primary focus of our garden will be to donate to those in need as a food bank garden.

As always, we look forward to growing and learning along with you! You might also be interested in joining our new, Victory Garden 101 Facebook Group to engage in more conversations and learning about vegetable gardening. What changes have you made to your garden plans due to the pandemic?