Squishy Squash

Question: My yellow summer squash is doing weird things this spring. Some are shriveling up on the ends, some have a fuzzy black growth on the ends, and others are just not growing but seem to get darker and tougher skins.

Answer: Congratulations, you have hit the squash problem jackpot or the squash disorder "perfect storm". In this case there are multiple reasons for the multiple problems. Let me take them in order:

First, poor pollination will cause poorly formed fruit and/or fruit end shriveling. Also, the dreaded calcium defeciency can cause similar symptoms as well. Cool soils can contributue to the lack of root growth and the lack of the plants ability to pick up the calcium.

Second, Choanephora fruit rot is favored by wet weather. Both blossoms and fruit are affected and fruit nearest the ground are more likely to become diseased. It is not unusual to find 30-40% of blossoms and/or fruit infected with the fungus. The growth looks like the picture above (from the The American Phytopathological Society website). On the plus side this disease is seldom long lived and will pass when weather conditions change.

Third, the very cool weather this spring (especially at night) has greatly slowed fruit enlargement and has led to slow growing fruit which matures (hence the darker color and tougher skin) without very much fruit enlargement. Pollination also affects fruit size and could be a contributing factor.

Warmer and drier weather will solve all the problems discussed and no treatments are needed.

Rhododendron Deadheading

I was out in the Birmingham Botanical Gardens admiring the last of the rhododendron blooms. The long and cooler than normal weather this spring has given us a long azalea and rhododendron bloom period. I think it is possible that the stress of last year may have also contributed to a big bloom show this spring. The plants looked stressed but they were filled with blooms. Sometimes when plants are under stress they will make a lot of bloom buds as a last ditch effort to reproduce itself. One way to reduce stress and to funnel energy into new growth is to dead-head old blooms. While out in the gardens we shot some video showing this task. Take a look here to see how this process is carried out.

The case of the missing tomato leaves.

One of my co-workers, David Hubbard had a question from a client who wanted to know what could have completely defoliated 36 tomato plants in a two night period. The damage was described as tomato stems and main branches remaining with no leaves or evidence left. My response was I felt it was too early for tomato hornworms or some other kind of caterpillar and it was likely a four legged rather than a six legged critter. (diagram from NCSU publication)

The client re-planted and decided to watch the garden the first night. He went out with a flash light and observed some bugs on the foliage. He treated the tomatoes with sevin dust and the next morning found large numbers of dead bugs at the base of the plants. He brought the bugs in for me to identify and they turned out to be vegetable weevils.

The interesting thing was the that these critters had never been a problem for this seasoned gardener of 30 years. When we discussed his recent gardening activities he reaveled one minor change in his normal modus operandi. Because of the drought of 2007 he had planted a large number of collards and turnips near his back porch where the water hose was available. Normally his greens were planted far away from his home. He recently destroyed the left over winter greens by tilling and then immediately planted tomato seedlings to the area. Upon investigation I noted that these greens were the host plants for the vegetable weevil larvae. My guess is when they became active the only food available were these tiny tomato plants and they completely stripped the foliage in short order.

The moral of the story is be careful to not jump to conclusion without a thorough investigation.