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Problem & Solution
July/August 2010

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Glyphosate Damage
Problem:  My tomato plants are 4-feet tall, thick and lush, and loaded with green tomatoes, but this problem has started in the last week or so (see photo).

Rhonda Austin
Dallas


Solution: Kevin Ong, plant pathologist, Texas A&M, says that the bleaching of the base of the leaves in your photos is a symptom that is consistent with glyphosate damage. Glyphosate is the active ingredient in Roundup and several other herbicides. Even if you haven’t used Roundup (or another glyphosate product) in or near your garden, perhaps you used a sprayer that previously contained Roundup. Very tiny amounts of glyphosate can have an adverse affect on tomatoes. There is not much you can do about that now. In the future, be sure to avoid using the same sprayer in the vegetable garden that you used to spray Roundup or other herbicides and avoid spraying Roundup in areas adjacent to your vegetable garden. It is even possible that a neighbor spraying from across the fence could have unknowingly caused your problem since glyphosate particles can drift onto your tomato plants from many feet away.

Shady Tomatoes
Problem: My above-ground garden is in full sun. The okra and peppers love it, but not my tomatoes. I want to put a shade over them. What value block is best for this area? I read the magazine religiously; however, I could have missed this article. If not, it might make a good one. Thanks again, and we love y’all’s work.

Griz Harkins
Boerne


Solution: We do not recommend using shade cloth or any other material to shade tomatoes because they require at least 6 hours of full sun to produce a crop. The one exception to that rule would be to provide shade to newly set out tomato transplants in mid summer until they become established. If your tomato plants are not doing well this spring then you need to dig deeper to find the problem. You could start by mulching the plants, maintaining even soil moisture and checking for signs of disease or insect damage.

White Lies
Problem: Please clarify: I was told not to plant any color of bearded iris near white iris because the whites are dominant and will cause the other irises to change color to white. Is this true or false?

Edna Brown
McKinney

Solution: False. Bearded irises do not change from their original color to any other color. They reproduce vegetatively as new rhizomes develop. So the color of the blooms will be the same as the parent. However, if the bed is not properly cared for, the white irises may flourish and choke out the others.

Stabilize Block Garden
Problem: I am interested in the article in the May 2010 edition — “Larry’s U-Block Garden.” We are in Victoria and have black gumbo, clay soil. As this stuff dries and gets wet, everything moves — fences, landscapes, trees, foundations, etc. We can’t just set something on top of the ground without tying it down. Any suggestions from you or Larry?

Joyce Henneke
Victoria

Solution: Larry has the same type soil as you do and his U-block garden has never shifted since it was constructed. Larry did put gravel over the soil and tamped it well before building the beds. You could probably do the same thing with either gravel or sand to help minimize shifting.

Snails
Problem: Our yard and garden is infested with snails and we can’t seem to get rid of them. Hope you can help!

Loretta Holt
Nolanville

Solution: Snails and slugs have been a problem for many gardeners this year, in part due to the unusually wet winter and spring we experienced. There are several insecticides that are helpful in controlling the garden pests, but we prefer to trap them using traps baited with beer. Just place some shallow dishes filled with beer in places where you have noticed the snails. The snails will crawl into the traps, consume the beer and pass out. Be sure to remove and destroy the pests on a regular basis. What you do with the leftover beer is up to you!

Goodbye Hosta Blooms
Problem: Although I like the hosta plants, I couldn’t care less for the flowers. Is there any reason I have to leave them on? I would prefer to cut them off instead of letting them flower.

Jennifer Hays
E-mail

Solution: According to William Scheick, author of our recent article on hostas, you can snip off the flowers, if you wish. Although some hummingbirds visit them, hosta flowers are of limited general bene­fit to wildlife. Moreover, because flower production is a costly extravagance for any plant — basically moving precious resources from bottom to top — preventing hosta flowering and fruition can conserve these resources and foster offset rhizomess.