Experts and BHG readers answer.
beautiful plant, no veggies
"Squash require cross-pollination for fruit to set. The first blooms on the vine are all male, and will not form fruit. Later on, the blossoms alternate between male and female (You'll be able to see a miniature fruit at the base of female blossoms.) If both male and female blossoms are present, but fruit is not setting, you may have to hand pollinate, if natural pollinators are not present. Use a soft-bristled artist's brush to transfer pollen from the male blossom to the female.
Peppers are particular about their preferred temperature range. When conditions are either too cool or too warm, they will not set fruit."