Desert’s dryness usually deters snails

If you have not been out to the Tonopah Community Garden and are looking for community involvement, then Oct. 15 might be a good day to mark on your calendar. There will be a Taste and Toast wine and cheese tasting event from 6-9 p.m. to help raise some money for the garden.

During this tough period, it is a good time to give back to the community that has given us so much. The garden is located at 715 N. Tonopah Drive in Las Vegas. Come and meet some great community-minded folks working at the garden.

Q: Do you have any idea how to get rid of snails? I have a factory. There are literally hundreds throughout my grass and planters. They are very small and we rarely see the large ones, so I'm not sure if they are regular snails or what. But I'd like to get rid of them because they grab onto the kids shoes which can bring them in the house.

A: Snails are not usually a huge problem here due to our lack of moisture and sparse plant growth. However in a garden situation where there is plenty of water and debris on the ground, they can get established and are usually brought in on nursery or garden materials.

The basic strategy is to minimize water by using drip irrigation whenever you can and cleaning up ground debris to remove hiding and egg-laying places. Traps can be put out, basically so that you have some central locations where you can find them and kill them.

Usually, once you get these traps established and conduct raids daily for about two weeks you will lower their numbers substantially. Then once or twice a week is all that is necessary to maintain lower numbers.

There are some devices, such as copper barriers and diatomaceous earth, that can be used to keep them out of specific places. Then there are the chemical baits containing metaldehyde and Sevin .

Q: My husband and I attended your seminar earlier this year regarding growing grapes and making wine. It was very interesting and helpful. We have been growing Thompson "tasteless" for about four years now and they are doing quite well, however, our second-year wine grapes, Cabernet and Black Spanish, appear to have black rot according to the Internet pictures. Can you tell me if this year's crop can be saved?

A: We don't have this disease west of the Mississippi to my knowledge. That is an East Coast grape disease problem. We have very few grape disease problems in our climate due to our low humidity and geographical isolation. It is more likely to be sunburn. Looking at the picture you sent, the discoloration is typical of sunburn and it seems to be on the side facing toward the sun.

When the berries are developing, make sure they are in the shade of the canopy as much as possible during the heat of the day. They should have as much indirect light as possible to help in color development (which also helps in the color of the juice or wine).

When you trellis the grapes, you want to make sure that the bunches are shaded from direct light as much as possible by the overhead canopy of the vines. We use a catch wire about 18 inches above the cordon wire to do this so that the fruit remains protected but still allows for plenty of indirect light. The fruit needs sunlight to develop good color and antioxidants.

There should also be plenty of air movement around bunches so that the few disease problems we have are minimized. We sometimes pull leaves off of the vine surrounding the bunches to increase indirect light and air movement.

Grape berries usually turn color (called veraison) in July through September depending on the variety. Most of our wine grapes are ready for harvest in late July and into most of August. Veraison also will turn the berry a different color as it spreads through the bunch, but I am not seeing this in your picture.

Not all the grapes will turn color at the same time, nor will bunches be ready for harvest all at the same time. In the extreme heat of July and August color development can be very spotty, with some bunches much further along than others.

Q: When should I cut my tomato vines back for a fall garden? How high above the ground should I cut them back?

A: You don't have to cut them back. They will begin to produce again as the temperatures cool this fall. However, if they have gotten too large or you want to reinvigorate them, then you can cut them back.

If you cut them back, make sure whatever you use is clean and sterilized. You can cut back about one-third of the plant just above some side branches. Cutting the plants back will cause them to grow vigorously as they try to re-establish the tops to their existing root system. Do not cut them back to the stems or they most likely will just die.

If there is fruit still on the vine that you want to harvest and cutting the vine means removing the fruit, then you might wait until after you finish harvesting. Then go ahead and cut.

Once you have trimmed the plant back, lightly apply some foliar fertilizers that focus on fruit production. This would mean using a fertilizer high in the middle number or phosphorus and lower on nitrogen. Apply this fertilizer in the early morning hours while it is still cooler and the sunlight is not so intense.

You want to stimulate some new growth but you want the nitrogen in the fertilizer to begin to fizzle out in a couple of weeks as daytime high temperatures cool.

You can apply a fertilizer to the soil, but these generally last too long and can cause your tomatoes to grow excessively before they bloom again. Foliar fertilizers are usually short lived and you will get flowers sooner after an application. Try mixing it at half the label rate.

Whenever you are growing vegetables you should be applying light applications of fertilizer when you are harvesting. You are taking away from the plant so you need to give something back to it to help it recover .

Bob Morris is a horticulture expert living in Las Vegas. Visit his blog at xtremehorticulture.blogspot.com.