Question:
I am trying to grow bush Peonies in large containers. They can reach about four or five feet in height, and the leaves start to brown at the edges. What can I do to prevent this year?Answer:
- This is a classic case of 'water stress.'
- The soil dries out, causing the plants to wilt; they are then watered and rehydrated. However, the cells at the outer margin of the leaf suffer too much damage to recover and turn brown.
- This damage occurs first at the farthest point the water must travel, at the top and sides of the plant. Wind and sun can quickly dry out these plants.
- You'll also find that fungal diseases such as Botrytis blight can cause leaves and stems to turn brown, while mildew creates a white film on the leaves.
- Additionally, plants that stay in the same container for 18 to 24 months will endure more stress than newly planted specimens due to having less soil and more roots.
- For your plants, I recommend removing them from their containers, pruning the root ball, adding fresh soil, and replanting them in the same containers.
- I suggest watering them daily when daytime temperatures exceed 80 degrees; otherwise, watering every other day should be sufficient.
- To manage fungal diseases, thinning the plant increases air circulation. Ensure your peonies are well-spaced to promote unrestricted airflow, which helps to dry out the moisture that fungi thrive on.
- Gardeners also worry when they see ants crawling over their peony buds, but the ants do not harm the plants; they are attracted to the sweet nectar of the flowers.
- Diatomaceous earth is a fine powder made from fossilized algae used for natural ant control. When ants come into contact with diatomaceous earth, they absorb the oils and fats from their exoskeletons, ultimately causing them to dry out and die.
- If you cut flowers for use indoors, gently wash them to remove any ants before placing them in a vase.
Question:
My hibiscus was damaged during the frost this winter. Although it was covered most of the time. There is some green under the bark, but no signs of new growth. What should I do?Answer:
- I’m not surprised that you haven't seen any new growth yet.
- It's early. The flush of new growth on evergreen ornamentals is beginning. Deciduous plants have leaf-out, and roses are in bud and bloom.
- However, Hibiscus requires warmer nighttime temperatures. Currently, temperatures hover around forty degrees at night, while fifty degrees is more favorable for Hibiscus. This applies to all tropical evergreens.
- The presence of green bark is a positive indication. I suggest doing nothing and reevaluating the situation in six weeks. By that time, you should observe signs of new growth.
- At that point, I would prune away any winter damage and begin your feeding schedule to promote further growth.