Gadenin日本語Get the appSupports go in before the buds fatten, not after
A fully double peony flower holds an extraordinary amount of water. Wet, a single bloom can weigh half a pound (200 g), and a stem carrying two or three of them bends to the ground in one heavy shower and does not stand up again. The stem is not broken, it is permanently kinked, and the flowers finish the season lying in the mud. This is the standard way a peony display is lost, and it happens over the course of a single afternoon.
Put the support in when the shoots are 8 to 12 in (20 to 30 cm) tall and the buds are still hard green peas. At that stage you can drop a ring or a set of stakes over the clump and the foliage grows up through it and hides it completely. Once the buds have swollen and the stems have arched outward, there is no way to install a support without breaking stems or bunching the plant into an obvious tied bundle.
A grow through ring set at about two thirds of final stem height works best for a mature clump, which reaches 30 to 36 in (75 to 90 cm). For a large clump, three or four canes around the outside with two rings of soft string, one at 12 in (30 cm) and one at 24 in (60 cm), holds it without pinching. Single ties round individual stems cut into them and are more work for a worse result.
Single flowered and semi double peonies with lighter blooms often stand unaided in a sheltered spot. Fully double types will flop, in every garden, every year. Judge by the flower form, not by how sturdy the plant looks in spring.
The ants are harmless and the buds do not need them
Peony buds secrete a sugary nectar on the outside of the sepals as they swell, and ants come to drink it. They are feeding, nothing more. They do not damage the bud, do not carry disease into it, and they leave of their own accord once the flower opens and the nectar stops. There is no reason to spray, wash or wrap the buds.
The old belief that peonies cannot open without ants chewing them free is simply wrong. Buds open perfectly on plants with no ants anywhere near them, and cut stems brought indoors open in a vase without any insect help at all. Killing the ants does no harm to the plant, but it does nothing useful either, and insecticide on an open peony flower kills the bees that do matter.
The one practical point is cut flowers. If you bring peonies indoors, cut them in the cool of the morning, hold the stems upside down and shake them, then stand them in a bucket of water outside for twenty minutes before arranging. That removes the passengers without any treatment at all.
Water, feeding and the yearly rhythm
An established peony is deep rooted and drought tolerant, and overwatering it does more harm than a dry spell. The period that genuinely matters is from the shoots emerging until the flowers finish, when the plant is building both this year's display and, invisibly, next year's flower buds. In a dry spring, give a mature clump 4 to 5 gallons (15 to 20 liters) once a week at the base and let the surface dry between times. Watering the foliage encourages the fungal stem rot that peonies are prone to.
Feed lightly and low. A balanced granular fertilizer or a bucket of well rotted compost spread in a ring around the plant, keeping clear of the crown, as the shoots emerge is enough for the whole year. High nitrogen feed produces tall soft stems that flop worse and flower less, and is a common self inflicted cause of a leafy peony with few blooms.
Disbudding is optional and it changes the character of the display. Each stem usually carries one large terminal bud with two or three smaller side buds below it. Remove the side buds while they are pea sized for one very large flower per stem, or remove the terminal bud instead for several smaller flowers over a longer period. Doing nothing is a perfectly reasonable third choice.
| Stage | What you see | What to do |
|---|---|---|
| Shoots emerging | Red shoots 2 to 6 in (5 to 15 cm) | Spread compost in a ring clear of the crown, weed carefully by hand |
| Shoots 8 to 12 in (20 to 30 cm) | Buds still hard green peas | Install the ring or stakes now, before stems arch |
| Buds swelling | Buds pea to marble sized, ants present | Disbud if you want larger flowers, ignore the ants, water in dry weather |
| Flowering | Buds showing color and opening | Cut for the vase at the soft marshmallow stage, keep water off the flowers |
| After flowering | Petals dropping | Deadhead to a strong leaf, leave all foliage standing |
| Late summer | Foliage full, no flowers | Water only in drought, no feed, no cutting back |
Keep a note of when it flops and how much it drank
Write down the date you installed the supports and the date the first flower opened. If those two dates were less than a week apart, you were late and next year you should be putting the ring in at least three weeks before you expect color. That interval is the whole trick of getting supports right, and it is repeatable from year to year on the same plant.
Note the weather at flowering as well. A season of storms that flattened an unsupported clump is worth recording next to the plant's position, because a spot exposed to prevailing wind needs sturdier support than a sheltered one and you will forget which is which by the following spring.
Finally, log the flower count. A mature clump gives a fairly consistent number each year once settled. A sudden drop points to shade from something that has grown up nearby, a crown that has been buried by successive mulching, or a plant that has been disturbed, and having the previous years' numbers is what turns a vague sense of disappointment into a diagnosis.