Q A caller planted beets that had a date of 2017. They were described as dark red beet on the package. When she harvested them, they were lighter in color and when cooked and cut into them they were cream to pale rosy color in parts. Two of them were as big as baseballs but most of them were more egg sized. She thinks she planted these same beets last year and they were red. Is this caused by them being older? Would they be safe to eat or just not as flavorful?
A The color of the roots should be consistent with the variety, even if the seed is a year old. I suspect that there was some error in packaging where some seed from another variety got mixed in with the seed that you purchased as a dark colored beet variety. Cooler temperatures or other weather variables may also play a factor. In either case, as long as the plants themselves look normal in appearance, the roots should be fine to eat.
Q I had someone bring some leaves from their peony in to the office in Gregory County. I’m not sure who to send them on to or ask. But they would like to know why the leaves on their peonies are doing this, and what they can do to remedy or fix the problem. (See photo.) Any help would be appreciated.
A This summer has been particularly warm muggy weather in many areas around the state. As the humidity levels rise, the incidence of powdery mildew has been on the rise as well. Powdery mildew can attack a wide variety of plants in our gardens and landscape but we see a greater incidence of the disease in plants like this peony but it can also attack other flowers dahlia, delphinium, phlox, snapdragons and zinnias; vegetables like cucumbers, pumpkins, squash, melons and peas; and woody plants like apple, crabapple, catalpa, elm, grape, lilac, oak, rose and Virginia creeper; and several types of turf grass. While many plants are potentially infected with powdery mildew, there are also many different species of powdery mildew fungi that are responsible for the infections. Just because one particular plant in your yard or garden has powdery mildew does not mean that particular kind of powdery mildew will spread to a different kind of plant. But if both plants are in a similar environment, then they both may develop the disease.
Many fungal diseases need free water on the plant in order for the fungal spores to germinate and begin to invade the plant. Some need a wound on the plant, in order to get inside the plant and spread. Powdery mildew fungi don’t need either one. But, they do need high humidity, about 70 — 90%, for several hours to develop and spread. Powdery mildew produces a powdery white mycelium that grows over the surface of the leaf that soon produces pin-head sized round fruiting structures that later turn tan to black. These fruiting structures can be moved by wind, insects, splashing water or physical contact from one leaf or plant to another. Warm daytime temperatures, in the 80 — 90° range, with dry soil conditions also foster disease development. Interestingly, free water on the plant actually inhibits development of the disease. But if the foliage dries off but then creates an area of higher humidity around the plants, this will increase the chances of having powdery mildew.
Leaves are the most commonly affected part of the plant attacked by powdery mildew, but it can infect any above-ground part of the plant, particularly succulent, young tissue like new leaves, stems or fruit. Using a nitrogen fertilizer late in the summer, when powdery mildew is most common, should be avoided since it will encourage more tender, susceptible growth to develop.
Powdery mildew damages plants primarily by impeding a plant’s ability to produce food through the process of photosynthesis. The powdery, white mycelium reduces the amount of light that can get through to cells inside the leaf where the green chlorophyll, that undergoes photosynthesis, is found. Leaves may also be malformed, especially if infected early in their development, or portions or whole leaves may just fall off the plant. Infected fruit may also be malformed.
The most important means of dealing with powdery mildew is by utilizing cultural control. Since powdery mildew is favored by high humidity, avoid planting susceptible plants in areas that are prone to being more humid. This would include areas that have poor air circulation, like inside a dense planting of shrubs or trees, in enclosed areas of a yard with little air movement or in dense shade of large trees or buildings. If possible, prune out extra branches to improve air circulation. Space plants well apart so foliage can dry out more quickly. Avoid overhead sprinkling, especially in the evening when it will take longer for plants to dry out following sprinkling. Avoid fertilizing plants when powdery mildew is present, so you do not encourage more susceptible, new growth to develop. Thoroughly clean up the garden at the end of the season and remove debris from the garden to reduce the number of over-wintering spores that might be present in the garden. And, look for powdery mildew resistant varieties of vegetables, flowers and fruit.
In addition to cultural controls, there are some chemical control options. Fungicides that contain sulfur are often quite effective, but you must be careful to follow label directions to avoid damage to leaves or flowers. Neem oil has also been found to work well on a variety of plants as well as other types of ultra-fine, horticultural oils. Triforine can be used for control on ornamental plants, like roses and lilacs. A relatively new group of fungicides that contain potassium bicarbonate can also be affective on a wide variety of plants. It is important to remember that like treating most other fungal diseases, fungicides like sulfur and triforine help to reduce the spread of the fungus but it will still be present and can spread again under the right conditions. So, treatment should start early and be repeated as indicated on the label to keep it under control.
Baking soda, sodium bicarbonate, similar to potassium bicarbonate, has become a popular home remedy. The usual recipe calls for about 1 to 2 TBS. of baking soda plus ½ tsp. of dishwashing soap or ultrafine horticultural oil in a gallon of water. Shake thoroughly and apply to plants using a spray bottle. Be careful to try this mixture on a few test plants or leaves first to be sure it does not damage the plants. If used in combination with a recent sulfur fungicide or with high temperatures, in full sun or to water stressed plants, can result in plant damage.
For additional information see: http://igrow.org/gardens/gardening/powdery-mildew-on-lilacs/
Brown spots on columbine leaves
Q This columbine has brown spots which have spread throughout the whole plant. (See photo.) There are other columbine plants in the same perennial bed which do not have this issue. What could be causing the spots?
A Spotting like this on columbine is fairly common. It is most often associated with heat or drought stress, particularly if the plants are growing in a sunny location. It is generally not a real problem for the plants since their foliage often dies back after flowering in the early summer. Providing extra water during dry periods can help to avoid the problem.
Often columbine will self-seed and some of those seedlings may not be as vigorous or drought tolerant as the original plants.
Q I am a resident near whitewood South Dakota in the Black Hills. I have a volunteer plant that popped up in my garden this spring, and I haven’t been able to identify it yet. At one point I thought maybe it was a pepper, but I am still unsure. I would like to get a little better idea if I should be letting it go or if I should be working on getting it contained and preventing it in the future. There are two of them identical. I will include pictures and if anyone could be of assistance, I would appreciate it, or if not if anyone could point me in the right direction for someone they know that maybe could that would also be appreciated.
A This looks like pale smartweed (Polygonum lapathifolium) or a closely related plant. The smartweeds are usually associated with wetter areas, ditches etc. but it can show up just about anywhere. It is an annual but it can produce a lot of seed so unless you really like it, I would suggest you get rid of it before all those little flowers produce their seed.
Vining plant taking over my shrubs
Q I have this light green, vining plant with white flowers that is growing over the top of many of the shrubs along the side of my yard and even climbing up into the trees. In some cases, it is probably 10 to 15’ tall! I am worried that it is going to harm my trees, choke them out or something. What is it and how do I get rid of it?
A One of the most frequently asked questions that I have gotten recently refers to a vining plant that looks like it is going to take over the world, or at least a few trees in the yard or a section of a shelterbelt. Sometimes it will grow along the edge of a corn or soybean field and cause a bit of trouble during harvest when it grows out and covers nearby plants. The plant has light green leaves and greenish-white flowers in clusters that are up above the foliage. The plant has tendrils which allow it to easily climb up on a fence, tree or shrub. The leaves look a bit like a maple leaf with several angular lobes to the leaf. The plant is called wild cucumber (Echinocystis lobata). It is native to the eastern part of our region and often grows in road ditches, shelterbelts, and near streams and ponds. It does have some value for wildlife as it provides cover for small animals and birds.
It is called wild cucumber because fruit looks like a small, rounded, spiny cucumber. The plant is in the Cucurbitaceae family so it is a relative of our garden cucumber, but I would not advise slicing any of the fruit up for a salad. The fruit is not very fleshy and usually has four seeds, about ¾” long inside.
I am impressed by this annual plant in that it can grow up to 15’ long in one season and literally cover small trees in one season’s growth. While it may look a bit intimidating, it does not really harm trees very much since it climbs by attaching itself to small twigs and branches with its tendrils. A few of the people I have spoken with about this plant thought it might be kudzu, but thankfully that invasive plant does not survive in our climate. If you want to control wild cucumber, just pull it out of the ground or cut the stem off near the bottom of the vine. Since it is an annual it will die with a good frost too. But, there will likely still be viable seeds left by this plant, so you can expect to see it again next year. If you don’t want it back, try to pull as much of the vine out of the trees and dispose of it while it is still blooming and has not yet had a chance to produce any seed. Watch for it to appear next year and pull or cut off the plants when you see it.