Gadenin日本語Get the appThe eyes sit barely an inch below the surface
Look at a bare root peony and you will see fat pink or red buds on the crown, at the point where the storage roots join. Those are the eyes, and they are next spring's stems. Set them 1 to 2 in (2.5 to 5 cm) below the finished soil surface and no deeper. In a mild climate with hot summers, keep to the shallow end at 1 in (2.5 cm). In ground that freezes hard every winter, 2 in (5 cm) is the maximum.
Deeper than that and the plant behaves exactly as though it were healthy. It makes strong stems, full foliage and a bush that looks better every year, and it never produces a flower bud. The crown needs a cold spell it can actually feel, and buried under 4 to 6 in (10 to 15 cm) of soil it is insulated from the winter chilling that triggers flowering. Nothing you feed it will fix this. The only cure is to lift the plant in early autumn and reset it at the right depth, and you then wait a further two to three years for it to settle.
Two things quietly deepen a peony after planting. Backfilled soil settles, dropping the crown another inch over the first winter, so plant with the eyes very slightly proud and let it settle to level. And mulch counts as soil: a 3 in (8 cm) layer of compost heaped over the crown every year buries it just as effectively as digging the hole too deep. Mulch the ground around a peony, never the crown itself.
Before you backfill, lay a cane or a straight stick across the hole at ground level and measure down to the topmost eye. Guessing by eye in a half filled hole is how most peonies end up 4 in (10 cm) down.
Dig the hole wide, and dig it once
A peony is shallow at the crown but deep in the root, sending storage roots 18 in (45 cm) or more down within a few seasons. Loosen a hole 18 in (45 cm) across and 18 in (45 cm) deep, then refill the bottom two thirds with the excavated soil mixed with a couple of spadefuls of well rotted compost. The plant will sit on that refilled base, so firm it before you set the root or the whole thing sinks over winter.
Keep raw manure and concentrated fertilizer away from the crown. Peony crowns rot readily in contact with anything actively decomposing, and a handful of bonemeal or a balanced granular feed mixed into the lower soil is all a new plant needs for its first year. Rich food at the surface encourages soft growth and, in a wet spring, the fungal stem rot that is the peony's main disease.
Choose an open, sunny position with at least six hours of direct sun and free draining soil. Peonies flower poorly in shade and rot in ground that stays wet in winter. Keep them well clear of established trees and large shrubs, whose roots will take the water and food long before the peony can. Space plants 3 ft (90 cm) apart; they reach that width and they need air moving between them.
| Item | Bare root division planted in autumn | Container grown plant |
|---|---|---|
| Depth to topmost eye | 1 to 2 in (2.5 to 5 cm) | Same as it sat in the pot, or shallower |
| Hole size to loosen | 18 in (45 cm) wide and deep | Twice the pot width |
| Spacing between plants | 3 ft (90 cm) | 3 ft (90 cm) |
| Best time to plant | Early to mid autumn | Autumn preferred, spring acceptable |
| Feed at planting | Compost and bonemeal low in the hole | Compost worked into the backfill |
| First flowers expected | Second or third spring | Following spring, sparsely |
Plant in autumn, and plant where it can stay
Autumn is the right season. The soil is still warm, the plant is dormant above ground, and new roots grow through autumn and early winter so the crown is anchored before spring. Plant six weeks before the ground freezes if your winters are hard. A container grown peony can go in during spring, but it will sulk through its first summer and give little or nothing that year.
Peonies resent being moved. A well placed plant lives for fifty years and improves every decade; a plant lifted and replanted stops flowering for two to three years while it rebuilds its root reserves, even when you do everything correctly. Treat the planting position as permanent. Walk the border, check the light through the day, and think about what will overshadow the spot in ten years before you dig at all.
Water the new plant in thoroughly to settle soil around the roots, then leave it alone. Autumn planted peonies need no further watering unless the season is unusually dry. Do not cut back or tidy the crown, and do not be alarmed by a completely bare patch of soil until well into spring: peonies are among the last plants in the border to break dormancy, and red shoots often do not appear until the daffodils are finishing.
- Find the eyes and count them Turn the root over and locate the pink or red buds on the crown. A division with three to five eyes establishes fastest. One with a single eye will grow, but adds a year or two before it flowers.
- Refill the hole to the correct height and firm it Backfill until the base is at the depth that leaves the topmost eye 1 to 2 in (2.5 to 5 cm) below finished ground level. Tread it firm. If you skip this the crown sinks over winter and you have accidentally deep planted the peony.
- Set the roots spread out, not coiled Lay the storage roots outward and downward across the firmed base. Never spiral a long root round the hole to make it fit; shorten it cleanly with a knife instead, and let the cut dry for an hour before planting.
- Backfill, check the depth again, and water once Fill in halfway, measure down to the top eye with a cane laid across the hole, correct if needed, then finish filling and water in with about two gallons (8 liters) to settle the soil.
- Mark the position clearly Push in a labeled marker. Peonies emerge very late and unmarked crowns get forked through, planted over or hoed off during spring bed work. This one minute saves a plant.
What to write down on planting day
Record the planting date, the exact position in the bed, and above all the measured depth from the finished surface to the topmost eye. In three years, when the plant is leafy and flowerless and you are trying to work out why, that single number tells you immediately whether depth is the cause or whether you should be looking at shade, competition from tree roots or simple immaturity.
Also note the number of eyes on the division and the source. A one eye division that gives no flowers in its second spring is behaving normally; a five eye division that gives none by its third spring is telling you something is wrong. Without the count, both look like the same failure.
From the first spring onward, log the date the red shoots first break ground and the date the first flower opens. Those two dates repeat closely year to year on the same plant and become your own local calendar for when to get supports in place and when to expect the display.