Q. Last season, I spread about 6 inches of hardwood sawdust on my pumpkin, squash and gourd garden to control weeds. The sawdust is still there and will act as a mulch for this season also. By using the sawdust, do I need to add any nutrients to my soil this season? If so, what should I add? – Myrna Sowers, Crawfordsville, Ind.
A. Uncomposted sawdust ties up the available nitrogen in the soil, so you will need to fertilize with one-half pound of nitrogen for every cubic yard of sawdust. You may choose to remove some of the mulch layer so that the soil will warm and dry more quickly. A three- to four-inch layer of mulch is ideal.
In the future, consider composting the sawdust for a year or two before putting it on the garden. And look for yellowing foliage as a sign of nitrogen deficiency.
Q. For the last two years, I have had problems with my tomatoes and tiger lilies. They both seem to be suffering from the same symptoms. The plants start out looking very nice. A few weeks into the season, however, the lower leaves of both start turning yellow and then eventually turn brown and die. This continues to travel up the plant. I get very little yield from my tomatoes, and the lilies don’t flower. What should I do? -Myrna Sowers Crawfordsville, Ind.
A. Do you have a walnut tree nearby? Both lilies and tomatoes are sensitive to damage by a chemical given off by walnuts. If no walnuts darken your property, the diagnosis becomes trickier. Tomatoes can be afflicted by several diseases and cultural problems that produce the symptoms you describe. Dry soil, too much shade, fusarium wilt and verticillium wilt are all possibilities.
The lilies are susceptible to cultural considerations and a virus. To reach a diagnosis, someone will have to see actual samples of the plant material. Take portions of the ailing plants to your county Extension office this summer. I’m sorry that I can’t be more helpful, but there are too many possibilities to make this diagnosis by mail!
Q. I enjoy your article and find it helpful. I need some help with my firethorns. I have two: one on the north side, the other on the west side. They look very healthy, but I never have very many berries. Can you help me with this? I love the bushes I see in the area with their lovely berries. Thanks. – Johanna Welch, Bennington, Ind.
A. Pyracantha, or firethorns, grow quite well in partial shade but require sun for maximum flower&emdash;and therefore berry&emdash;production. Are they receiving at least six hours of sun each day? You may need to prune nearby trees to increase the light or relocate the pyracanthas. Also, consider the fertilization of the surrounding area. If the firethorns are receiving too much nitrogen, either directly or applied to the surrounding turf, they will produce foliage at the expense of flowers.
Q. I have a honey locust tree in my back yard. It is a huge tree. It first spread out everywhere. It used to look so full and healthy, but now it looks so spindly and empty. It has a lot of deadwood. My son built a box around it with decorative timbers, and we filled it with white marble rocks. Could that be the reason it looks so spindly now? – Donna Pratt, Jamestown, Ind.
A. Honey locusts are susceptible to a number of problems, including pod gall midge, borers, mites and especially webworms. Look at trunk and foliage for signs of trouble, and bring any samples in to your county Extension office.
Constructing the box could have caused damage by disturbing the surface roots, compacting the existing roots or reducing air exchange to the roots, but an insect or disease problem is more likely.
Q. I’m sending a picture of a plant that I’ve always known as a snake’s tongue or mother-in-law’s tongue. I don’t know the correct name. Anyway, I have one that is two years old, and it bloomed in November. It had one spike come up in the middle of one of the plants. (Blooms on the spike were tiny, white bell shapes.) They spread, so I have several in one pot. I’ve never seen or heard of one blooming before. Is this unusual or do they just seldom bloom? – Della Jones, Dubois, Ind.
A. Sansevieria is generally grown for its foliage but does occasionally bloom, usually in the spring. It’s very easy to grow and tolerates a wide range of exposures and even neglect. Someone gave it the common name of mother-in-law’s tongue. Is it because it’s so sharp? Or because you can’t kill it? Or because it’s so tolerant and quietly continues no matter how you treat it? I’ve heard all of these explanations. Your answer probably depends upon your mother-in-law!