Gardening: Zucchini plants still can be planted, but they will need plenty of watering amid heat

If you still have space in your garden or an empty place on your patio, it’s not too late to plant zucchini. The ground is warm enough, and it looks like we are in for some hot weather so they should grow fast.

Zucchini is one of the easier squash to grow. In a garden, the plants need about a 3- to 4-foot square space to spread out. If you are growing them in a container, you will need one about 24 inches in diameter as the plant has a good-sized root system.

The plants will need a well-drained soil rich in compost. Plant three to four seeds 1 inch deep in a cluster. With the soil and weather as warm as it is they should sprout in about a week. After they have set out their first true leaves, thin them to the two strongest seedlings. The plants will need about 2 inches of water a week applied in one or two deep soakings to reach the deep roots. The plant will grow a few leaves and then stop growing for a while as it develops its root system. Feed the plants every three to four weeks with a fertilizer low in nitrogen but high in phosphorus and potassium.

Some of you who planted your zucchini early might be seeing flowers and small fruit emerge. Zucchini plants produce both male and female flowers. The female flowers will have a bulge at their base. Usually the plant will produce many male flowers before the female ones appear to ensure good pollination. Because the first half of June was quite cool the few female flowers that did emerge probably didn’t get fully pollinated. As a result, the fruit might form but it will quickly shrivel up.

Squash borers are the major pest of zucchini and they are emerging now. The adult borer will appear first as a half-inch long wasplike bug with an orange abdomen with black dots. It has metallic fore wings and clear aft wings. The adults will lay their tiny, flat, brown eggs at the base of leaf stems. When the larvae hatch they will bore into the stem to feed and in the process, plug up the stem causing the plant to wilt.

Controlling the pest isn’t always easy. Watch for the adults flying around during the day, then check the base of the stems for signs of eggs or holes made by the larvae. If squash borers weren’t a problem last year, cover the plants with floating row cover to keep the adults out. If you did, skip this as the bugs will emerge under the cover. Remove the cover when you have a lot of female flowers so the bees can pollinate them. Spray the base of the plants once a week with insecticidal soap or a Bacillus thuringiensis bacteria product like Dipel, Thuricide or Green Step to kill the larvae before they bore into the stem. Avoid chemicals like Sevin that are toxic to bees.