Most central San Joaquin Valley gardeners plant peppers and eggplants at the same time they put in tomato transplants – usually in late March or early April. But peppers and eggplants require higher temperatures to set flowers and fruit than tomatoes. Temperatures in March and April are usually too cool to give peppers and eggplants a good start; vigor is poor, growth is sluggish and early blossoms drop off. Peppers and eggplants often don’t set and hold a good crop of flowers until mid-May unless heat caps or row covers are installed to help retain heat and speed up growth.
Peppers and eggplants (and squashes, melons, and cucumbers) are a little behind flower production schedule this year due to the lovely, mild May weather we’ve had. The low amounts of flowers on these heat-loving vegetables is a concern. We can expect a really hot spell soon with temperatures above 100 degrees. Peppers and eggplants will set flowers when temperatures are below 100 degrees, but flower drop will occur with higher temperatures, and bees will reduce foraging and pollinating when it’s that hot.
Poor or incomplete pollination is common during hot weather. Pepper fruits will show normal color, but have a flatter shape and few or no seeds inside the fruit if pollination is poor; eggplant fruit will fail to develop.
Keep the soil evenly moist, fertilize eggplants and peppers monthly with a half cup of a low-nitrogen food, and harvest ripe fruit to keep plants in production. Cut stems to avoid breaking brittle branches. Peppers can be picked either green or red, but red bell peppers such as “Yolo Wonder” taste sweeter and contain twice as much vitamin C as green peppers as well as increased amounts of Vitamin A
Harvest eggplants when the flesh has a slight give to it. Press the skin lightly; if you see a shallow indentation, the eggplant is ripe.
Members of the cucurbit plant family (squashes, melons, cucumbers) have sticky pollen that is not spread by wind. Only bees can pollinate cucurbits by carrying pollen from male flowers to female flowers. When bees aren’t flying during hot spells in late spring and early summer, incomplete pollination will cause shrunken, malformed fruit and decreased yield. Dedicated gardeners can hand-pollinate melons, squashes and cucumbers by using a clean paint brush to gather the yellow pollen themselves from the male flowers and brushing it onto the center of the female flower or by cutting off the male flower and rolling it onto the stigma inside the female flower’s center. Hand-pollinate in the early morning, using only freshly opened flowers.
Male squash flowers are born on a longer, slender stem; the female flowers have a shorter stem. Melon and cucumber flowers are smaller than big, showy squash flowers. The male flowers are born in sets of three to five on short stems; the female flowers are single and show a miniature fruit at their base.
The first flowers to appear on melons, cucumbers and heirloom summer squashes are often all male which die off without setting fruit. (Hybrid summer squashes produce female flowers first). Pollination on cucurbits won’t occur until the female flowers appear a couple of weeks later.
Avoid spraying pesticides during the daytime hours when bees are actively foraging.
Elinor Teague: firstname.lastname@example.org