How to grow peonies
Peonies do like a sunny location with well-drained soil and good air circulation around the plant is important. Growing in these conditions help peonies avoid their only serious disease problem, botrytis commonly know as peony wilt. Like other fungal diseases, botrytis is present in most soils but usually only becomes a problem if the plant is weak and the weather has been unusually cool and wet or plants have been placed too close together.
Ideally plant in the plant in early spring or autumn. Prepare the planting area by incorporating organic matter such as garden compost or well-rotted manure. On poor soil apply a general fertiliser, avoid planting too deeply, make sure that the top of the crown is approx 5cm (2in) below the soil level If planting pot grown plants, it is generally best to plant at the same soil level as in the pot. Water regularly when rain is lacking during the first year to help the plant become established especially if planted in spring or later in the season.
Depending on the variety of peonies you are growing, you will probably need to provde them with a peony plant support frame for when the flowers are in full bloom. This is especially important with larger blooms which can become waterlogged and extremely heavy. Peony plant supports should be put in place early on in the growing season, before the plants get more than a few inches high. Once the plant is in full bloom, it is much harder to set up an effective support system and the damage may have already been done.
It will often takes a few years before you see an abundance of flowers on any new plants but once they do start to bloom, you can look forward to a lifetime of beautiful flowers. Peony plants rarely need dividing but if a clump does become too large for its space autumn is the ideal time to divide it. Cut back the foliage and carefully lift the entire plant out of the ground. Use a sharp knife to cut apart some of the plant, making sure to create generous clumps of roots with at least three to five eyes per clump. Then reposition the original plant back in the hole, taking care not to break off any of the relatively brittle roots and make sure you water it in well.