Q: Something is eating holes in my rhubarb leaves. The leaves turn yellow and spindly. I thought that the leaf portion of a rhubarb plant was poisonous. What can be done for my plants?

A: The poison in a rhubarb leaf is oxalic acid and is a poison when you eat too much. Oxalic acid gives many foods a tart or bitter taste. It is added to candies and found naturally in cranberries, spinach, bananas and many other foods. In its white crystalline form it is used as a household stain remover and bleaching agent. Medically, it rapidly reduces blood coagulation and can be used to treat hemorrhaging and jaundice.

Poisoning symptoms range from a burning mouth to coma. Its effects can be neutralized by eating foods high in calcium like eggs, beans and milk.

You are right there are not many pests that eat rhubarb. A small half-inch long weevil called the Rhubarb curculio may be partly responsible. It does not feed on the plant but does poke holes all over to lay eggs. The young hatch and join the adults to feed on a plant called dock, which is a common weed. I also wouldn't be surprised if slugs are at work here too.

Rhubarb plants like good drainage and often decline in vigor if not divided after about five years. Divide them in the fall and plant them in a raised bed with lots of compost. They are heavy feeders so fertilize regularly and irrigate frequently. Do not let the flower stalk go to seed by cutting it off at the base of the plant.

Q: The tomatoes in my garden are usually loaded, but this year they don't have very many fruit. What is going wrong?

A: Tomatoes are sensitive to weather. Hot and dry weather causes tomato flowers to fall off. Tomatoes and other garden vegetables will drop flowers if the daytime temperatures stay above ninety degrees for much of the day for several days in a row. They will do the same thing when the nighttime temperatures drop below fifty-five degrees in the fall.

If the flower is only partially pollinated the fruit that develops may be misshapen. Pinch off the odd looking fruit since they will not fully develop. When the temperature goes back into the right levels the plants will begin producing again.

Tomatoes will drop flower buds and small fruit when the plant does not receive enough water. Keep the soil wet between waterings by having several inches of mulch over all the soil within two feet of the plant. Install drip irrigation tubing under the mulch to water just the roots and not waste any water. You can also try a homemade drip system by poking a small hole or two in a gallon plastic milk jug and letting it leak out over the roots. (Use water not milk)

Another problem that tomatoes will get when they are watered and then left to dry out repeatedly is called blossom-end rot. The bottom end of the tomato away from the stem will turn black and sunken. This rotten mess will also develop on peppers, squash and watermelon. This disease problem develops from other root damaging problems as well. If you cultivate and pull weeds near the roots it may develop. Excessive water or fertilizer salts damage the root hairs and they do not pick up enough calcium from the soil and the fruit may get blossom-end rot.

If your tomato fruits have been developing, but not getting large, they may be in need of a little more moisture. If you give them too much the fruits may swell and crack in circular rings. They are still edible if just a little ugly.

Email questions to Jeff Rugg at info@greenerview.com. To find out more about Jeff Rugg and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.