Dividing and Planting Peonies
The best time to divide and plant a peony is September. Here are a few tips for successful peony division and planting.

To Divide a Peony
Cut plant stems down to ground level.
Carefully dig plants and shake gently to remove soil.
Cut clump into sections making sure that each section has 3-5 eyes and a portion of the root system.

To Plant a Peony
Dig a hole 18 inches deep and 18 inches wide.
Break up any large clods of soil and add organic mater, if needed.
Add 1/4 cup 5-10-5 fertilizer to half the soil and place this soil into the bottom of the hole. Add soil without fertilizer to adjust the soil height so the peony division may be properly placed.

Plant the peony so that the eyes are approximately 2 inches below the soil surface in the northern U.S.
Water thoroughly throughout the fall and mulch with 3 inches of straw in late fall. Remove mulch when growth resumes in the spring.

Where to Plant Peonies
Select a sunny, well-drained location for your peonies. They will tolerate some shade, but should have at least a half-day of sunshine. The best blooms are usually found on plants growing in full sunlight. Do not plant near large trees or heavy shrubs where they would be robbed of necessary moisture and plant food. Plants may be spaced from two to four feet apart according to desired effect in the landscape. If you wish to develop large specimen clumps, space them four feet apart. Peonies prefer a soil that tests 6.5 pH.

Fertilizing Peonies
If your ground has been properly enriched at planting time, there will be little need for further fertilization for some years. The type of soil will determine the frequency. Porous soils lose their fertility faster than others, as it is washed out by the rains. Keep all fertilizer away from the crowns of the plants; there are no feeding roots there. Spread it over the area where the roots grow, from six to eighteen inches from the crown and thoroughly incorporate it with the soil. Use it with discretion. Over-fertilized plants will not bloom well and soon run their course. About a handful of commercial fertilizer or one or more of bone-meal to a plant will be plenty.

Watering Peonies
Water your peony plants immediately after planting so that the soil settles well around the roots. During the spring months, there is usually enough moisture in the ground for peony plants, but if several weeks pass without rain, give them a good watering once every two weeks. This should also be done during the dry summer months after the peonies have bloomed to ensure a good crop of flowers the following year.

Winter Protection
Newly planted peonies should be given winter protection for the first winter after planting. After the ground has frozen, in fall, give them a covering of straw or marsh hay about three inches deep. This covering will protect the plants against heaving due to alternate thawing and freezing. Remove the covering very early in spring. Established plants need no winter protection. When foliage has turned brown in fall, after the first heavy frost, cut the plants down as near to the ground as possible. Burn all the old stems and leaves as a protection against disease.

What to expect from your Peonies
The first spring after planting, a standard division will make one or more stems six or more inches high. Do not be discouraged if growth is low and only one stem appears. It may bloom and it may not. Do not worry if it does not. Many growers do not allow a plant to bloom the first year. If you allow the plant to bloom, cut the flower as soon as it fades directly below the bloom. Do not allow seed to form. First year peony blooms rarely give a true picture of the variety.

The second year, the number of stems is usually double the number that came the first year. Growth is taller. If there are blooms, they are nearer normal. Cut all blooms immediately after flowering, with short stems. Some varieties take several years to produce normal flowers.

The third year growth generally doubles that of the second year. Blooms should be normal in every way. Do not cut the stems too long. While the finest flowers are produced from plants 4-10 years old, many varieties have been known to give exhibition blooms for 20 or more years. Plants that have been well cared for will even outlive the gardener. If they are forced into abnormal growth by the use of stimulants, they will give out in a few years.

Why Do Peonies Fail to Bloom?
There are many reasons, but here are the most common:
Plants are too young and immature. Let them develop.
Plants are planted too deep. If eyes are more than 3 inches under ground, raise to proper height of 2 inches.
Large clumps planted without proper division. Dig, divide into small or standard divisions and plant.
Plants have too much competition from surrounding trees and shrubs.
Plants have too much shade which encourages tall leafy plants and no blooms. Move.
Too much nitrogen was applied which encourages foliage not flowers. Phosphorous or potassium will strengthen roots.
Plants are undernourished. Buds show, but do not develop. Fertilize to add strength.
Buds killed by late frost.
Excessively hot weather. Late, full double varieties often fail from this cause.
Buds attacked by thrips will turn brown and fall. Spray to prevent this.
Buds that become water logged will turn brown and refuse to open. Bagging would help.
Ground is too dry. Water down to the bottom of roots.
Roots infected with nematodes or root-knot. Destroy.