An article on growing Peonieshttp://ohioline.osu.edu/hyg-fact/1000/1241.html
All Peonies have five or more large outer petals called guard petals and a center of golden, pollen-bearing stamens. Peonies are classified according to flower form: single, Japanese, anemone, semi double and double.
Peonies flowers can be harvested only after three years of planting. Commercial production starts with 5th year onwards and remains in production for more than 25 years. Remove all flower buds up to three years before taking commercial production. It helps to increase plant vigour and leaf canopy area.
The application of fertilizer should be proportionate to the crop needs. They should be well fed in early spring and again soon after flowering requiring up to 100gm/m2 of artificial fertilizer. About half handful of low nitrogen fertilizer per plant is adequate, exceeding it may cause weak stems and reduced blooms. Application of fertilizer mix with a NPK ratio 12:32:16 is beneficial for plant growth. Fertilizer should be mixed well with the soil but kept away from direct contact with the roots.
Tree Peonies are a semi woody spp. originated in china. They are popular in Japan. These are really shrubs of 6-8 feet. Their stem remains alive in winter except in extreme climate. They bloom mostly early. During their flowering time they show heavy plate size (up to 20 cm) blooms on long slender stems at the top of leafy branches.
Peonies are one of the most beautiful herbaceous perennial flowers of the home garden. These long lived plants can survive from generation to generation, flowering each year with grace and vigour. Peonies have a limited range of colours chiefly white, rose, pink, crimson and yellow.