Care of Peonies



Herbaceous peonies grow from tuber divisions. When tubers are first planted they put out fine feeder roots and then develop storage roots. When you buy a tuber, these fine feeder roots may or may not have already started to develop. Find a nice sunny, open, free draining spot and double dig or fork down deeply until it is nice and loose.

Peonies are hardy plants – they like a free-draining mineral rich soil. If you determine your soil is deficient in nutrients, trace minerals and potash based fertilisers can be added sparingly during planting. We recommend you always use organic products for your own and the earth’s wellbeing.

When planting tubers, the buds must be max 5cm (2 inches) below the surface of the soil as they won’t flower well if planted deeply. Place the tuber in the shallow hole, cover with soil, firm down and water well.  To flower well, a peony needs 80 days of cold on the ground above its tuber. This cold does not have to be hard frosts, but the temperature needs be between 0-7°C for at least 500 hours.

It is important to maintain a moist soil, never waterlogged, for your peony over the first year to ensure the feeder roots grow well and convert to storage roots (or tubers) to establish a strong plant. Once established, as long as peony plants are given water when it is really dry, they take very little care and practically look after themselves, giving joy and countless blooms for years.

The main disease affecting peonies is botrytis, which is spread by raindrops and cool  humid weather and can spread rapidly throughout a crop. It attacks the leaves, stems and buds making them rot and go brown. You can use copper based fungicides to control but be aware, these build up copper in your soil over time so should be used wisely. We use a product called Botryzen locally made in Dunedin, which has proven to work well for us, that effectively acts as a barrier fungus for preventing Botrytis getting access to the flower parts. It is a good idea to also remove infected parts of the plant and move them away from the peonies to compost for other crops. Botrytis is weather related, and is more problematic when there is wet weather during flowering.


Leave the plants to die down naturally in Autumn/Winter, so that the roots can retain nutrients from their stems and leaves.

In late May/June, once frosted, cut each stem at most an inch above the ground. Be careful not to pull the stems out, as future flower buds may come out as well. If you do, cut off the stem above the buds and plant in a pot – it’s likely it will take root if looked after. It is recommended that peony leaves are removed from the plant and burnt or composted, however we chop and mulch on the growing area to build organic matter in the soil and it works well.


If the blooms are cut at the right time, peonies are a very long lasting flower with a vase life of up to two weeks. However, cutting at different stages of opening can shorten or lengthen their vase life. When cutting flowers, you are looking for petal movement at the top of the bud. Find nice fat buds with colour showing at the top and before cutting squeeze the bud from each side. If you see the petals move, then cut the stem. If the petals do not move, even though colour is showing, the flower will take much longer to come out, and in some cases doesn’t come out at all. All varieties are very different, and some are quite big and partly opened before petal movement is seen, whilst others seem to have just started to show their colour and the petals will move. Picking a bud when it is half open will only shorten its life by a day or two so that is fine. When picking a full blown Peony it is hard to know how many days it has been out, and the vase life will be affected, but as long as it is not faded or old looking then you should get about 5 – 6 days of beauty in the vase.

Try to pick the flowers early in the morning or in the evening, rather than in the heat of the day.

When picking a bunch that needs to be kept for a while or to be given away, a little extra care will be very helpful to them. As soon as they are picked put them in a bucket of water with a few added ice cubes if available. Keep them in a cool place where sun and light is limited. If travelling a long distance, put them on damp newspaper with a chilly pad at the base of the stem and roll up lightly. Then roll in more newspaper ensuring the top  and bottom are folded in so the flowers are encased in a cool damp situation. Choose a large size vase as Peony are a heavy flower. Recut stems to good length for  the vase. Snap off any lower leaves. NEVER let the flowers run out of water as it is hard, and often  impossible, to resuscitate them. To give longer vase life, keep in a cool place and it is believed that the addition of an ice cube a day makes for lasting and happy cut Peonies.