Watermelon - yellowing leaves, split fruit

Asked August 15, 2020, 8:03 AM EDT

This watermelon patch originated from a melon that was left to decay in the yard last fall. Recently, the leaves in the center of the patch have started to yellow and I just discovered that some of the smaller melons are splitting open. Is there anything I can do to save the remaining fruits (particularly the larger ones)?

Montgomery County Maryland

3 Responses

Hi- the leaf yellowing could be caused by a number of different factors-
1. the need for fertilizer; watermelon typically needs to be fertilized after fruits start to form. Plus, the excessive rain in June and August may have leached out some nutrients.
2. Older leaves naturally turn yellow and ie as the season progresses. This process is accelerated by stressful environmental conditions.
3. There are a number of foliar watermelon diseases that cause leaf spots and lead to yellowing and browning.

Fruit splitting could be caused by excessive soil moisture. It's hard to tell from the photos but a number of animals will feed on watermelon fruits. There's not much that you can do to prevent splitting other than watering plants (at the base to avoid leaf wetting) if the weather turns dry.

If this volunteer watermelon plant germinated from a seed that was inside a commercial watermelon it is almost certainly a hybrid cultivar. The daughter plants this year will not be identical to the mother fruit. This may also be contributing to the fruit splitting problem.

Jon

Thanks so much for the rapid response. I believe the seeds were from a plant I purchased and attempted to grow last year - before the squash bug invasion took over! (At least this year, I knew how to deal with them!)

we have drip hoses installed, so watering shouldn’t be an issue - but we haven’t watered in ages because of all the rain. However, I also haven’t fertilized the watermelon patch. What should I use?


Thanks again from a very beginner gardener.

Hi- we suggest a complete fertilizer (contains nitrogen, phosphorus, and potassium), preferably where the % of nitrogen is equal to or greater than the % of the other two major nutrients. One example is cottonseed meal (6-2-1), an organic fertilizer.

You may enjoy this blog article on fertilizing vegetable crops:
https://marylandgrows.umd.edu/2020/05/15/vegetable-plants-to-gardener-feed-me-and-ill-feed-you/
Jon