When planting Peonies plant as soon as they are obtained, being careful to set the division so that the top of the buds will be from 1-1/2 to two inches below the final soil grade after the plants are watered and have finished settling.
If planted too deep you will probably get pretty foliage with a few or no blooms, and if too shallow, the buds will be exposed and are likely to get broken off by Old Shep when he serves notice on a stray cat or rabbit.
You should expect blooms from three to five eye divisions the first season. Only seven of the 60 varieties I planted in my garden a few years ago failed to bloom the first year. The plants made a splendid display of flowers the third season after planting.
Digging and dividing large, old peony clumps is no easy task, as most gardeners have learned. If the freshly-dug clump is left exposed to the air for a while, the roots will become less brittle and are more easily handled without breaking. The soil which is tightly held by the roots is best removed with a stream of water from the hose.
Do not simply cut the clump in half and plant the two peonies without removing any of the old large roots. Such divisions depend upon the old roots for nourishment and seldom bloom. The clump should be cut into smaller divisions, usually with from three to five eyes, some of the older roots removed and the others shortened to about six inches.
This method stimulates the production of new roots which increases the plant’s vigor and productiveness. A stout butcher knife and a hammer are good division tools. Established plants may be fertilized in early spring with a handful of balanced plant food applied in a ring around each plant and stirred into the soil.
To Preserve Peony Color
Most peony flowers fade in sunlight and if left to open and stand in the sun they lose much of their delicate beauty. If you wish to use peonies for display in a flower show or as a bouquet in the home, cut the flowers and let them open in the dark or at least in partial shade. Do not cut stems so long that all of the leaves are taken with the stalk. This would tend to weaken the plant.
Peonies which are properly planted and maintained are seldom bothered by diseases. The foliage is hardly ever attacked by insect pests. Plants should be carefully watched and if any disease occurs the affected parts should be removed and destroyed.
Root knot, leaf spot and botrytis blight are the three most common ailments. Root knot can be avoided by planting clean, healthy divisions in disease-free soil. New plants should not be set in an old bed where root knot has occurred. If the plants are properly spaced, very little damage is done by leaf spot.
Botrytis blight is likely to be the most serious peony disease and sometimes in orchid plants. It affects stems, buds and leaves just like in caring for orchid plants. Young stalks in early spring suddenly wilt and fall over, and young buds turn black and dry up. Later on, larger buds which become infected turn brown and fail to open up.
For control, remove and destroy all infected parts as soon as they appear. Cut off all tops near the crowns in the fall and burn. If severe infestation has occurred before, remove the upper two inches of soil around the plants and replace with fresh disease-free soil.
Also as a preventive measure in the spring, spray the young shoots as soon as they appear, with Bordeaux mixture 2-2-50 or a copper fungicide mixture. Two or three successive sprays should follow at weekly intervals.