What makes my zucchini yellow and brown on the young ends?

Question:Some were fine and some grow with yellow ends.
Then they are rotten and there are ants harvesting pollin from the flower, would that have anything to do with it ?
Sacramento

Answers:
The symptom you're seeing is called "Blossom-end Rot". There are two reasons why you're seeing your young zucchinis turning brown with yellow ends;

1) Calcium defficiency; Your zucchinis don't have enough calcium to develop properly. To correct this, make an application of dolomitic lime around the base of your plant and water-in. The lime supplies the necessary calcium and magnesium needed.

IF you don't want to apply dolomitic lime..you can spray calcium onto your plant. This results in a more immediate response to the blooms and fruit. Some organic gardeners even spray milk as a source of calcium.

Both the dolomitic lime and calcium sprays can be found at most of your hardware/garden shops.

2) Lack of Pollination: A common reason for rotting and shriveling zucchini is lack of pollination by bees. Pollination is absolutely required for fruit set. Without pollination, the fruit that grows will yellow, shrivel, rot and die.

The zucchini has a male flower and a female flower, which must be pollinated in order for you to get proper fruit. To hand pollinate, break off a male flower, remove its petals to reveal the yellow pollen on its pistol, then roll the pollen onto the center stigma of the female flower.

You tell flowers apart because female flowers are larger and have a baby fruit behind their petals. The male flowers grow on a long stem and are smaller.

Some people use a cotton swab or artist's brushes to hand pollinate.

Hope either or both of these will help solve your problem. IF you have any further questions or concerns, please feel free to contact me directly. GOOD LUCK!

-Certified Professional Crop Consultant with over 30 years of experience and a Degree in Plant Science