Tree Peonies Grow Successfully† in Minnesota by Harvey Buchite growing plants in Zone 4 on well drained sandy soil.
I canít believe I waited so many years before trying to grow tree peonies because I believed what I read in so many of the books and articles written for northern gardeners. Contrary to what I read they are hardy, long lived beautiful flowering shrubs.† They come from mountain habitats often with cold winters and drier summers.† They always are found in areas of good drainage mostly among other shrubs.
When I saw a rather large bush with exotic looking leaves in the garden of my gardening friend Jean I could see that the tree peony was more than a few years old.† In fact I believe she said it was more than 25 years old and that it had dark red flowers.†
Thatís when I began to plant tree peonies!† First an un-named pink got me started.† It turned out to be Hana Kisoi one of the easiest to grow and bloom with great big large pink flowers.† But the flowers are only a part of the joy you get from your tree peonies.† The spring foliage is exotic with the edges of the leaves outlined in precise red to contrast with pale to dark green leaves.† The buds are often speckled with rose dots as they begin to expand to an up-side-down top shape.
At first I covered them carefully in the fall for winter protection and found out later that the protection was not necessary except to keep hungry rabbits from eating the stems in the winter.† Later I added a white, Renkaku, then a red, Hoki, then a yellow, High Noon, and then a maroon, Shima Daijin, and then ... some new ones from China and even some tree peony species that I grew from seed including P. lutea and P. suffruticosa.†
Soil preparation always pays off for me on the sandy soil that I have to garden in.† I begin by adding compost or peat moss and always try to prepare a hole bigger than the roots of the plant.† The next important thing is to plant the tree peony DEEP!† As deep as 3-4 inches below the grafted portion with at least two of the eyes on the stem just below the soil.†
Your most important factor in success of growing tree peonies is to get them off the herbaceous nurse root and onto their own roots.† To do that you have to plant them deep.†
Once planted they should be given a nice wood chip mulch to conserve moisture and the soil should be kept evenly moist.† The first year I see little growth.† But the second year when the tree peony is making its own roots the plant will double and triple in size to 3-4 feet across so give them room. One common mistake of new tree peony growers is to cut the plant back in the fall.† Not only is this not necessary but you are cutting off next years flower buds!†
As far as a site to grow I have seen them growing very well on the east side of a house and in dappled shade.† When a wood mulch is used I have even grown them in full sun.† On my sandy soil I have had leaf scorch but the plants bloomed well and put on better growth than the plants I have in shade that are competing with neighboring tree roots.
While quite winter hardy tree peonies do begin growth very early in the spring and once growth has started they are subject to frost damage like any actively growing plant.†
The solution is easy, cover the plants with a light weight blanket over night until the temperatures are above freezing.† Remove it during the day if it is to be above freezing to allow the plant to continue healthy growth.†
This habit of beginning early spring growth can be modified by planting in a shadier protected spot that actually slows early spring growth.† The north side of a building is sometimes
recommended for this
Some books mention them preferring a slightly alkaline soil, but I have not seen much difference growing them in a slightly acidic soil.†
Yellow varieties; like High Noon and the pink variety Hana Kisoi seem to be the fastest growing,† most white varieties like Godaishu and Renkaku are vigorous too while the red flowered varieties and purple flowered varieties are less so,
although they make fine plants in time.
I have noticed a greater number of Chinese Tree
Peonies showing up listed for sale and would welcome any comments from our membership on their growth.
†We have 12 varieties planted out for trial at the nursery and some at home.†
Those planted at home really suffered as our family was away for a month during the hot dry part of the summer.† So the lesson is to make sure you have back up waterers when you are away for vacation, or donít blame the plants for failing.
I am becoming more interested in these most beautiful early blooming members of our peony family and have started seed from the semi-double pinks, reds and purples for planting out in our woodland display in the future.
Give tree peonies a try I think you will like what you see.