Female zucchini fruits that aren't pollinated rot and die. In order to help control fruit rot, put a 2- to 3-inch-thick layer of clean, fresh straw beneath zucchini plants but not touching their stalks, and ensure new fruits are supported by the straw as they develop. Water zucchini plants' soil regularly so that the soil is constantly moist but never sodden. Sounds like Blossom End rot. My problem is with my zucchini, I grow it in containers on my sun deck where I have had great success with tomatoes in the past so I thought I would try some zucchini this year along with the tomatoes. Have something to add? The flower petals of an affected zucchini plant can remain attached, and usually the rest of the fruit is unaffected. Relevance. Please share your solution! Female zucchini fruits that aren't pollinated rot and die. 18.5 % min phosphorus 24% max calcium 20% calcium. Erratic watering causes blossom end rot in zucchini fruits. If the soil drains poorly, then grow zucchinis on small hills 6 to 9 inches high. Causes. Zucchini Rotting on the Vine? The larvae of the squash vine borer, Melittia cucurbitae, burrow into the stems of plants such as squash, gourds, pumpkins, and zucchini. Ready to pick 40 to 50 days after sown, zucchini (Cucurbita pepo) can bear heavy harvests, but poor weather and calcium deficiency sometimes cause rotting. Rotting Blossoms. A graduate of Leeds University, Jenny Green completed Master of Arts in English literature in 1998 and has been writing about travel, gardening, science and pets since 2007. Plan the perfect garden with our interactive tool →, Missouri Botanical Garden: Blossom End Rot of Cucurbits, University of Wisconsin Cooperative Extension: Blossom End Rot, Kansas State University Research and Extension, Johnson County: Zucchinis -- Not That Easy to Grow Anymore, Iowa State University Extension: Ask the ISU Garden Experts About -- Zucchini Rot, Grass Spiders and Iris Borers. Blossom-end rot is caused by a … This happens at ground level early in the season and can be discouraged by wrapping the young stems in aluminum foil to protect them from the adult borers. Grow zucchinis in full-sun sites and well-drained soil rich in organic matter. Zucchini plants begin to produce fruit in early summer in cold... Low Bee Activity. Zucchini gets about three inches long and than drys up. This lack of calcium in the soil is … In the past they have been fine. Zucchini fruits rot when lying on wet ground. Zucchini plants growing in the most favorable conditions produce the healthiest fruits. Zucchini fruits are picked young when they're about 6 to 8 inches long and 2 to 3 inches in diameter, depending on the variety. Blossom end rot is a calcium deficiency that is recognized by the secondary issue of the dark rotting area caused by a fungus. Bees usually pollinate zucchini, but they're less active than normal during cold, rainy weather. Preventing Problems. Zucchini Blossom end rot or is a common cause of zucchini rotting, so is inadequate pollination Calcium levels being too low in the soil. I have had poor success with growing Zucchini plants that produce zucchini. Learn which plants thrive in your Hardiness Zone with our new interactive map! I would like to know why my zucchini plants look great with lots of flowers and fruit but when the zucchini get about 3-4 inches they start to rot or go soft? www.gardeningknowhow.com/.../solutions-for-common-problems-growing... Will this work for Zucchini Rot? Ready to pick 40 to 50 days after sown, zucchini (Cucurbita pepo) can bear heavy harvests, but poor weather and calcium deficiency sometimes cause rotting. Blossom end rot begins as a small watery bruise at the tip of a zucchini fruit and often spreads and covers the whole end, causing a black or brown sunken depression that can turn moldy. Favorite Answer. Space plants 24 inches apart, and fertilize the soil with a ready-to-use, slow-release, 14-14-14 granular product applied at a rate of 1/4 pound per 10 square feet when transplanting plants or once while seedlings grow strongly.