Why are my peonies overrun with ants (it's normal!)

Why are my peonies overrun with ants (this is normal!)


Cultivated and revered in Asia for many centuries, the peony has charmed human beings for a very long time. Some gardeners and avid gardeners worship her and consider her the queen of flowers.

Peony Kopper Kettle Height: 70 cm Width: 80 cm Flowering: copper in June Hardiness: zone 3

Most peonies require more than 4 hours of sunshine to bloom abundantly. They can mostly tolerate partial shade, or even light shade in some cases, but their flowering is generally reduced.

On the other hand, peonies do not tolerate constantly wet soil. They prefer soil rich in organic matter, fresh and perfectly well drained. When planting a peony in heavy clay soil, it is imperative to amend it with compost. A peony should be planted in a large hole which has a width equivalent to three times the diameter of the root ball, while the depth should be equivalent to one and a half times the height of the root ball, in a potting mix consisting of a half of existing soil, if it is of good quality, and half of compost.

Peonies take four or five years to reach maturity and can then remain in the same place for several decades without being divided. In fact, the less a peony is disturbed, the better off it is.

The tops of peonies' roots should always be flush with the ground. It is therefore absolutely essential not to plant these perennials too deeply, otherwise they will not flower. 

A few tips

The upper part of the stump should never be covered with more than 2.5 cm of lightly compacted soil. The roots of peonies sold in containers are usually already laid out at the correct depth in their pot. At the time of planting, all you have to do is place the top of the clod of soil at the level of the existing soil.

When planting, be sure to provide plenty of compost for the peonies. In the years following their planting, spread a thickness of 2.5 cm of compost at their base each spring. Attention ! however, avoid placing this amendment directly on the stump of the peonies. 

It is essential to put the compost around the plants at a distance of about 15 cm from the stems. At the time of spreading, you can also provide your peonies with three or four (100ml) handfuls of a slow-release, potassium-rich, naturally-derived fertilizer that has a formulation closer to 5-3-8. Potassium promotes the formation of flower buds.

Ants at the service of peonies

Just before flowering, it often happens that peonies are literally invaded by ants. Fear not, these friendly critters do no harm to peonies. The ants are rather beneficial since they make war on all the insects that covet the peonies in their care. As a thank you, the peonies feed the benefactor ants by offering them nectar secreted by glands located at the base of the sepals that cover their flower buds.

Thin-leaved peony (Paeonia tenuifolia) Height: 60 cm Width height: 70 cm Flowering: red in early May Hardiness: zone 4

Peonies with single flowers

The many cultivars of peonies available on the horticultural market display various types of blooms, ranging from large double flowers to delicate single flowers, including semi-double flowers.

Unfortunately, large double flowers of some peony cultivars are very heavy and crumble to the ground after rain, making them particularly unsightly and requiring the use of stakes.

Peony Blaze Height: 80 cm Width: 80 cm Flowering: red in June Hardiness: zone 3

Peony Bowl of Beauty Height: 90 cm Width: 90 cm Bloom: pink and white in June Hardiness: zone 3

Peony Coral Sunset Height: 90cm Width: 90cm Flowering: Peach-pink in June Hardiness: Zone 3

For their part, peonies with single flowers are usually less prone to crashing into the ground. Their flowers are composed of 5 to 10 petals that surround a heart filled with stamens. Some cultivars sport stamens that do not produce pollen. These floral parts, called staminodes, are not completely transformed into petals.

Other peonies, very unique, have a heart filled with large petaloid stamens that look a little more like real petals.

Among the hundreds of cultivars of single-flowered peonies, here are five that have a excellent hold, even in rain and wind.

Tree Peonies

Tree peonies are quite fascinating plants that form woody stems. Under mild skies, some of these peonies can reach up to 3 meters in height. On the other hand, in a harsher climate like ours, they rarely exceed 1.5 meters. It is a mistake to think that tree peonies are fragile plants, since many cultivars can be grown in zones 4 and 5 without too much difficulty, sometimes even up to zone 3. Here are two that will do wonders in your garden.

Tree peony High Noon Height: 1.50 m Width: 1.50 m Flowering: yellow around the end of May Hardiness: zone 4

Shima-Nishiki tree peony Height: 1.20 m Width: 1 m Flowering: pink and white towards the end of May Hardiness: zone 4

Itoh hybrids

Several crosses between the tree peony Alice Harding, whose flowers are yellow, and the lactiflora peony Kakoden, with large double white flowers, executed in 1948 by the Japanese hybridizer Toichi Itoh, have led to the creation of a new generation of peonies with yellow flowers. 

As a result of Mr. Itoh's work, some hybridizers have developed several other intersectional peony hybrids. Vigorous and hardy, Itoh peony hybrids sport strong stems that are very resistant to rain and wind.

Caucasian peony (Paeonia mlokosewitschii) Height: 90 cm Width: 90 cm Flowering: yellow in mid- May Hardiness: zone 4

Peony Bartzella Height: 90 cm Width: 90 cm Flowering: pale yellow in mid-June Hardiness: zone 3