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How to Prevent Blossom End Rot in Zucchini Squash by Hand Pollinating

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Blossom end rot is a condition that occurs in some garden vegetables where the end of the growing vegetable where the blossom is suddenly rots, ruining it. This is often caused by calcium deficiency in the soil and/or lack of water. A third possible cause is insufficient natural pollination by insects. This article explains how to manually hand pollinate your zucchini squash to ensure adequate pollination.

Get up early. Zucchini squash flowers are wide open first thing in the morning but close up tightly later in the day. Before you start, take a look at your plants. If you see very few insects buzzing around the flowers you know that your time is about to be well spent.

Find one of the male flowers. Zucchini squash have separate male and female flowers. The male flowers are on long stems.

Pick a male flower. Peel back or break off the petals to expose the pollen-covered stamen. The pollen is messy so try not to get it on your fingers.

Identify the female flowers. These flowers are on short stems that are actually miniature fledgling zucchini.

Carefully rub some pollen from the male flower onto the central pistil of each female flower. You may want to mark the flowers with a piece of ribbon or string tied loosely around the stem so that next time you know which ones you have already pollinated.

Zucchini Grow?

The zucchini plant produces large, dark green leaves. Mature leaves display silver-gray spots and streaks on the surface. There are a number of different varieties of zucchini. Both female and male flowers grow on each zucchini plant, with at least three male flowers for every one female flower. It is easy to tell the difference between the two. Each male flower has a pollen-producing stamen in the center. It should be harvested when it is still young and tender, usually between 6 and 8 inches long. Fruit is usually ready to pick in about 60 days. Picking zucchini encourages growth. To slow fruit production, leave one or two zucchini on the plant. Seeds prefer soil with a pH range between 6.0 and 7.5.


Early in the season, the zucchini plant starts by putting out only male flowers, so don't be concerned if that's all you see at first.

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