Tree Peonies

By: John Degroot

May 30 2009

Tree Peonies - Garden Clippings for May 30, 2009

Why it is called a Tree Peony is anybody’s guess.  Even calling it a shrub is a stretch, because I’ve never seen one over 4 feet tall.  Ours was about 4 ft high, but last fall it was inadvertently pruned down to the ground.

Fast forward about 6 months and our Tree Peony is now about 3 ft high, and laden with 21 huge flowers. 

Tree Peony (Paeonia suffruticosa) is a sun loving shrub like perennials with woody stems that remain fully exposed to winter.  Flowers at 6 or 7 inches diameter are bigger than those of the regular peony, often drooping as a result of their own weight.  Flower colour is pink, white, yellow, red or purple.  The flowers of Tree Peony are so magnificent, they are certain to turn heads.

Leaves of Tree Peony are similar to the regular peony, but a little bigger.  Their course texture can become quite dominant in the garden, particularly when planted among lighter textured perennials.

In the landscape, I recommend using Tree Peony sparingly.  Its flowers are so large, bright and impressive that it can appear too overbearing.   That’s not a problem in my backyard where so much else is vying for attention.  The flowering period of less than a month is short, so if I become tired of the Tree Peony’s dominance, I need to be patient.

Like the normal herbaceous peony, Tree Peony wants to be planted in a sunny spot.  It will tolerate dappled shade, but flowers might be less productive.  Avoid planting Tree Peony near big trees where it will have to compete with the roots of other hungry plants.

All Peonies like a spot with rich soil at good depth.  In sandy soil I recommend digging out a wheelbarrow of sand to the depth of one foot, and replacing it with triple mix or compost.  After planting, add a layer of mulch over the compost to help retain soil moisture.

In clay soil, it is not necessary to dig as deep.  Mix compost or manure with some of the existing soil and work the soil to a depth of 8 inches.

Tree Peony is fond of moisture, but doesn’t like to be waterlogged.  If your soil is clayey and does not drain easily, plant it on a slope or small hill so the excess water runs away.  Both regular peony and Tree Peony doesn’t like to be planted too far into the ground.  If your Peony does not flower, it is probably planted too deep.

Peonies love fertilizer.  Add bone meal to the soil at planting time and once the peony is established, fertilize annually with any all purpose granular flowering plant food.