By Janice Brown
Can we just talk squash here for a moment? I just love squash! I love growing it. I love eating it. I love everything about it. Squash grows relatively well here in Texas, but there are two problems that can be a pain with growing this vegetable, so we will also talk about pests & diseases here too.
Squash comes in many different varieties such as the yellow summer squashes, zucchini, acorn, spaghetti, patty pan, cushaw , and butternut. Pumpkins are also a part of the squash family and can be grown in much the same way as its smaller siblings. Those of you who are a little further north have a better chance at growing pumpkins than those of us who are closer to the coast because you are less susceptible to powdery mildew.
Understanding and Preventing Pests
The two problems that plague squash are powdery mildew and squash vine borers. One is a disease and the other an insect. Powdery mildew is a fungus that begins as a white powdery growth on the tops and bottoms of leaves and turns leaves yellow soon after. It spreads rapidly, so at first sign, start treating. The good thing is organic copper fungicides work really well on getting the disease under control. Since we had such a warm, dry winter, mustard greens in many of the gardens I manage had powdery mildew. I used Bonide Copper Fungicide and it worked well. The best thing to do is just get a good organic fungicide and begin a regular spraying routine after planting to prevent the disease from forming.
The next issue is the loath worthy squash vine borer. This nemesis of mine comes in a small package, but does big damage. It looks like a small wasp, with a red body and black wings. It does its damage by laying eggs on the squash plant stem. When the larvae hatch, they bore into the base of the stems of the plant and begin to eat the tissue in the stem. The result is that your plants look healthy and are full of squash one day and the next day they’re dead and you don’t know why. If you look closely at the stems and see a tiny hole with what looks like sawdust around it, it’s a squash vine borer.
There are several ways to combat this pest. First, I suggest covering plants with row covers until stems get hard enough that the larvae can’t bore into them. This also prevents the adult from laying eggs on the stem. However, this also keeps pollinator insects from getting in to pollinate the flowers from which the squash develops. So you can hand pollinate by taking a cotton swab and using it to rub the center of each flower to collect and transfer the pollen. This is what bees usually do for us as they gather nectar.
Other methods of control include:
- Vigilantly keeping watch for tiny holes with brown “sawdust” around them. As soon as you see one, shine a flashlight under the stem to illuminate the borer on the inside. Once you’ve located it, stick a pin right through that little bugger! I know this seems cruel, but once you’ve seen the damage it can do you’ll be more than okay with this.
- Cutting larvae out by slitting stems with a knife and stabbing the borer. Bury the slit/damaged stem in the ground and hopefully it will root and you won’t lose the plant. This works best with vining plants.
- Wrapping the stems with strips of nylon stockings, to prevent the larvae from getting in them.
- Trapping the adult moths with yellow sticky traps. They’re attracted to yellow.
- Getting rid of finished vines and tilling the soil in the fall and spring to get rid of overwintering pupae because these can hatch and damage next year’s crop.
- Planting squash in a different location each year, so that if some pupae do overwinter in the soil, they won’t find the new plants.
- Planting extra squash. Some for you and some for the bores. There are only so many eggs they can lay and they shouldn’t be able to damage all of your plants.
- Planting really early (March) and then again really late (August) to get harvests while they’re not as active.
Squash can grow in two ways, on vines and on upright plants, usually referred to as bushing squash. For small gardens, bush types are better because they don’t need as much space. Vines can quickly take over, but if borers damage vines, it’s easier to bury parts of vines to regenerate growth.
Plant seeds or transplants in March and April after danger of freezes are over. Mix a good well-balanced fertilizer into soil prior to planting. All squash need good drainage, so planting in a raised bed or hilling up soil is a must. To hill, mound up a hill about 6inches high and plant 2-3 seeds in a group about 3-4 feet apart. Once plants start to grow, you will thin groups to one healthy plant. As soon as blooms occur fertilize with a high nitrogen fertilizer. For example, a 7-0-0. Keep fertilized from then on with the balanced fertilizer every 2-3 weeks.
Note the harvest size on packages when planting to determine how big fruit should be for harvesting. Most summer squash is ready at 4-6 inches zucchini at 6-8. Different varieties will be different sizes, but make sure to pick any variety, before they start to get hard. The smaller, the tenderer so don’t worry about picking too early.
On the Grow is a garden coaching service launched by Janice Brown to teach people how to be successful gardeners in the sometimes difficult, Gulf Coast climate. On the Grow provides garden education for the home gardener, children in outdoor classrooms, neighbors in community gardens, and employees in workplace gardens. Whether you want a new idea for a girls’ night out, a new way to engage children in nature, or want to implement a fresh wellness program in your company, On the Grow is here for you. Your coach will take you step by step teaching you the basics, while presenting you with a fresh perspective by helping you experience the healing benefits of gardening. Our mission at On the Grow is to help everyone experience the joy of a garden and build a greater connection to Mother Earth. Connect with One The Grow on Facebook and Twitter!