Fresh Layer of Top Soil on Tree Peonies
Freshly Applied in February
There's only one kind of peony that you can't plant too deep in the South - a tree peony! Most peonies grown in the South (herbaceous peonies) need to be planted with the eyes at ground level. You need to be very careful not to plant them too deep or they will not bloom. The eyes (small pink growth buds) of the peony need to be close to or right at the soil surface so they can collect chilling hours during the winter, enabling the plant to bloom. These peonies are the most common type of peony, herbaceous peonies - the ones whose foliage dies back to the ground every fall/winter.
However tree peonies are a totally different story. Tree peonies have woody stems that persist above ground year to year, and the flower buds develop on these above ground woody stems. Since the buds develop in the cooler above ground air (not within eyes or growth buds at the warmer soil/ground level), the tree peony buds are much more easily able to collect the chilling hours they need to bloom in our Southern climate. Since the buds are above ground on the stems, they cannot be buried in too deeply in the warm earth. Most tree peonies are grafted tree peonies (a branch that is cut from a mature tree peony specimen and is fused with a root from an herbaceous peony). These grafted tree peonies really need to be planted deeply for 2 very important reasons.
Important Reasons to Plant Your Grafted Peony Deep
1. The herbaceous root (or nurse root) that has been grafted to the tree peony stem must be planted far enough underground so that it never has a chance to sprout herbaceous foliage.
(You're trying to grow a tree peony, not some ugly flower from an herbaceous root stock).
2. The tree peony stem needs to be planted as far as possible underground so that it can attempt to grow roots of its own. These tree peony roots can only grow from the tree peony stem. So if you never plant the tree peony's stem below ground, it will not have a chance to grow these tree peony roots. Allowing it to grow its own roots will give the tree peony the opportunity to really take off and establish itself.
Fresh Layer of Top Soil on Tree Peonies
2.5 Weeks Later in March
To this end I like to put a fresh layer of top soil / organic compost around all of my tree peonies every year or two. As you can see I just put this fresh top soil out 2 1/2 weeks ago, and the tree peonies are already enjoying it. Adding this new soil makes sure they are still planted deep enough to attempt to grow some roots of their own, and it also adds a fresh layer of nutrient rich soil right over the tree peony's roots. You can also take this opportunity to sprinkle a little slow release organic fertilizer around them as well. If you do this, I would recommend sprinkling the fertilizer first, then adding the top soil / organic compost on top (or mixing it in). Have you fed your tree peonies yet this year? If not, now is a great time to do so - right before the foliage and blooms appear, giving your tree peonies the nutrition they need to be be best they can be. So what are you waiting for? Your tree peonies are calling you...
