This is the Q&A for the Yard and Garden show for June 24, 2016. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 5, 2016. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.
Guest Host: Jim Kalisch, Insect Diagnostician for UNL Extension
1. The first caller of the day has summer squash that grows about 3 inches long then they get soft and fall off of the plant. What would cause this?
A. This is probably blossom end rot. This is an environmental condition where the blossom end of the fruit of the plant rots, just as the name implies. This condition occurs often in the beginning of the season and will fade out later in the growing season. Blossom end rot is caused by a calcium deficiency in the fruit. In Nebraska, there is rarely a lack of calcium in the soil. Blossom end rot occurs when plants cannot pull calcium up quickly enough for developing tissues. Calcium must be dissolved in water to move within a plant, so dry soils can increase the problem.
2. A caller has tomatoes that the leaves are starting to curl up. They have buckets around the plants and each night they fill the bucket up with water. They also have white spots on the pumpkins. What is wrong with these plants and how can they be salvaged?
A. The water regime being followed is not the best practice. The buckets are holding a lot of heat in around the plants and filling each of these buckets every night is giving the plants a great deal of water. It would be best, this late in the season, to remove the buckets to reduce heat stress and use a sprinkler for a couple of hours or soaker hose for a few hours every other night to give the plants the right amount of water. The white spots on the pumpkins could be either powdery mildew or sunscald. Leave them alone, it should fade out and it will not cause a great deal of damage to the plants.
3. This caller has cucumbers and squash that the blossom end of them are rotting and then they fall off the vine. What would cause this?
A. This is blossom end rot. This is an environmental condition where the blossom end of the fruit of the plant rots, just as the name implies. This condition occurs often in the beginning of the season and will fade out later in the growing season. Blossom end rot is caused by a calcium deficiency in the fruit. In Nebraska, there is rarely a lack of calcium in the soil. Blossom end rot occurs when plants cannot pull calcium up quickly enough for developing tissues. Calcium must be dissolved in water to move within a plant, so dry soils can increase the problem.
4. A caller has peppers that had one bloom and now they are not setting any peppers on the plant. He fertilized it earlier this spring. What would cause this?
A. This would be due to low pollination. In this heat the insects are not moving around as much to pollinate. Give it time and the plants should begin blooming in a week or so.
5. This caller has a pin oak that the leaves are curled on the edges. What is wrong with this tree?
A. This could be from a gall gnat. This will cause the leaf margin to roll tightly. It could also be from herbicide drift. There is no control for either problem and the tree should outgrow both of these problems.
6. An email came in with the following question: The other day I found a fly on my dog’s head. When I went to grab it off, there was blood on her. Upon closer inspection, it looked more like a cross between a fly ad a bee. It’s triangle-shaped. What is it, how can I protect my dog?
A. This could be either a robber fly or a horse or deer fly or a stable fly. All of them can be kept at bay with fly repellent sprays or collars. These contain pyrethrins, essential oils and other ingredients not harmful to dogs. DEET is not advised for pets. It would be best if the dog owner to got information from a vet. Other tactics would be to reduce or eliminate fly breeding substrates, such as lawn clippings, pools of water, etc.
7. A caller planted string beans this year from both new and old seed. For some reason, the new seed seems to have more vigor even though they are planted right next to each other in the garden. Is it true that the new seed is more vigorous than the old seed?
A. Not necessarily. If the 2 plants were different varieties that would make a difference. Seed stored correctly should grow just fine for a few years after original sale. However, if the seed is stored in a location of high humidity or high temperatures, that can reduce the vigor in the seed.
8. This caller has a hanging basket of petunias. The buds on the plant are brown and full of black “balls”. She cut the plant back and put Sevin insecticide on it. What would cause this? Does she need to cut the buds off of the plant?
A. This is probably tobacco budworm. The black “balls” are probably fecal pellets from the caterpillar. Sevin may not be effective on this pest, so try Bt to kill only caterpillars and not harm any pollinators. Cut off the bloom to encourage new blooms to grow.
9. A caller has tomato plants that have grown to 4-6 feet tall. Now the leaves are curling and some are turning brown/black. What would cause this?
A. This caller has been using a hand wand to water at the base plant individually for a few minutes. This is not enough water for such large plants. It would be better to do a deep watering with the use of a soaker hose for about 4 hours 2-3 times per week or with a sprinkler for 1-2 hours 2-3 times per week if natural rains do not occur. Vegetables need about 1 inch of water per week for optimum growth. A little over that is fine, but we don’t want more than 2 inches, unless it comes as rain that we can’t control.
10. The final caller of the day has potatoes that were bored through the stem. What could that be and how can it be controlled? This caller also has green beans with yellow spots on the leaves and the beans are very curled rather than straight. What would cause this?
A. The potatoes have stalk borer. This insect pest should be about through with their damaging stage so there is no need to control it. As for the green beans, the leaves have a leaf spot fungus, there is no need to control it in a home garden, it should fade soon as the weather has warmed up and dried up. Remove these infected beans, that could be due to the hot weather that has caused a malformation in the growth of the beans, it should fade as the season continues on.