Q Last spring my peony had buds, but the buds never opened. My neighbors had their lawn sprayed at about the same time, and I'm wondering if pesticide drift could have damaged my peonies and kept the buds from opening.
A It's unlikely that pesticide spray kept your peony buds from opening. Spray drift from pesticides such as 2,4-D can damage plants, but the more common symptoms would be twisted or distorted new growth. You would also see pesticide damage on the entire plant, not just the flower buds.
A more likely cause for bud failure on peonies is a fungal disease. Botrytis is a fairly common fungal disease that can affect peonies, including the buds. Infected buds may turn leathery brown and fail to open. Often a fuzzy gray mold develops on affected buds or foliage. Botrytis is most prevalent during cool, damp weather. Several other fungal diseases may also affect peony buds as well as leaves, stems and roots.
The best preventative for fungal diseases is sanitation; remove and throw away (don't compost) any infected leaves, stems or buds as soon as you notice fungal symptoms. Also cut back and remove all old foliage in the fall.
Peonies need good soil drainage. If your plant is in overly wet soil, consider moving it to a spot with better drainage and good air circulation. September is the best time to dig peonies for relocation or division.
Q I want to plant more bulbs, wildflowers and perennials, but we have lots of deer in the yard. Can you suggest some deer-resistant plants?
A There is no guaranteed deer-proof plant, but deer do seem to have preferences when sampling goodies from the landscape. There are regional differences in deer browsing, and probably even differences in individual tastes within a group of deer. And, if deer are hungry enough, they will eat plants they might otherwise avoid.
That said, here are some suggestions for plants that are less likely to become dinner for the deer:
Ornamental onions (Allium)
Grape hyacinth (Muscari)
Calla lily (Zantedeschia)
Anise hyssop (Agastache)
Butterfly weed (Asclepias tuberosa)
Bleeding Hearts (Dicentra)
Foxglove (Digitalis )
Globe thistle (Echinops)
Hardy geranium (Geranium)
Lenten rose (Helleborus )
Bee balm (Monarda)
Russian sage (Perovskia atriplicifolia)
Lamb's ears (Stachys byzantina)
Oriental poppy (Papaver orientalis)
Purple coneflower (Echinacea purpurea)
QCan star magnolia be planted on the north side of a house?
AStar magnolia (Magnolia stellata) will do fine with a northern exposure as long as it is far enough away from the house so that it won't be in deep shade during the growing season (April through September). A northern exposure can actually be beneficial, because it may delay blooming by a few days to a week. This is helpful because star magnolia blooms quite early in the spring, making the opening flowers susceptible to damage from a late freeze. A slightly delayed bloom time means there's less chance that a hard frost will turn the beautiful white blossoms to brown mush.
Nancy Rose is a horticulturist, writer and photographer. To ask her a gardening question, call 612-673-9073 and leave a message. She will answer questions in this column only.