Weeping Cherries are two trees grafted together. When the lower one starts winning, the homeowner’s ornamental slowly disappears. Subordinate pruning fixes it.
Weeping Cherry trees are one of the iconic ornamentals of the South Jersey spring. They’re also one of the most commonly mismanaged ornamentals on residential properties — for a specific structural reason that has nothing to do with disease and everything to do with the way the tree was made in the nursery.
View from the Field · Paul Biester · Tree Awareness
“Here we have a Weeping Cherry. As you can see, this slim structure here weeps down and emanates from this grafted portion of the tree. What you have here is parent stem tissue that has sprouted and is now growing up — and will eventually choke out the grafted portion. This is not an ideal situation for this tree, and at some point that should be mitigated. So we have to set about subordinate-pruning these. There are three — one, two, three — stems that are growing out below this grafted portion. The tree should really just be this section and the graft. As you can see the sunken area here, and these are growing from some old epicormic sprouts — or epicormic sprouts that are dormant buds underneath the bark — not something everybody picks up on. If your weeping cherry looks like a cherry tree that’s wearing a skirt, oftentimes that’s what happens.”Paul Biester · NJ LTE #408
The botanical reality of a Weeping Cherry tree is that it’s two trees grafted together. The bottom is a sturdy upright cherry rootstock — usually Prunus avium or Prunus serrulata. The top is a weeping cultivar — Higan Cherry or Yoshino Cherry in weeping form — grafted onto the rootstock at a specific height (usually 5–6 feet) to create the umbrella-like cascading silhouette homeowners want.
The graft union is visible on a mature tree: a slightly swollen knot or sunken area where the upright rootstock meets the weeping crown. Above the graft is the weeping cultivar. Below the graft is the rootstock. They’re different cultivars on the same trunk.
Cherry trees produce epicormic shoots — new growth from dormant buds embedded in the bark of older wood. On a Weeping Cherry, these shoots can emerge anywhere on the trunk. When they emerge below the graft union, they’re shoots from the rootstock — not the weeping cultivar. They grow upright, vigorously, with the parent rootstock’s natural growth habit, and they’ll eventually outcompete and overtop the slower-growing weeping cultivar above the graft.
This is what Paul’s referring to with the “cherry tree wearing a skirt” description. The weeping crown is still there, but it’s been swallowed underneath an upright rootstock canopy that grew up around it. The homeowner often doesn’t recognize the problem because the tree still looks like a cherry tree — just an oddly-shaped one. Eventually, if left unmanaged, the rootstock canopy fully chokes out the weeping graft, and the tree reverts to being a non-weeping rootstock cherry.
The intervention is called subordinate pruning. The goal is to favor the grafted weeping crown by suppressing the rootstock shoots that are competing with it.
Step 1: Identify the graft union. Find the slightly swollen or sunken area on the trunk where the rootstock meets the cultivar. Anything growing below this point is rootstock and should be either removed or subordinated.
Step 2: Remove or shorten rootstock shoots. If a rootstock shoot is small and recent, the easiest call is to remove it cleanly at the trunk. If a rootstock shoot has been growing for several years and has become a substantial limb, removing it entirely will shock the tree — the right call is subordinate-pruning, reducing it to a small fraction of its current size to suppress vigor without removing it all at once.
Step 3: Promote the weeping crown. The cultivar above the graft gets the standard ornamental-tree pruning approach: remove dead, damaged, or crossing branches; thin to allow light through the canopy; maintain the cascading silhouette by selective tipping where branches have lost the weeping character.
Step 4: Schedule the cycle. Rootstock suppression is not a one-and-done operation. The dormant buds in the rootstock will continue producing new shoots every spring. Annual or biannual visits to remove emerging shoots are the right cadence for a high-value Weeping Cherry on a residential property.
Three common mistakes:
Removing rootstock shoots too aggressively at once. If the rootstock has been growing unchecked for years and the shoots have become substantial limbs, removing them all in one season is heavy pruning that the tree may not recover from. The correct approach is staged subordination over multiple seasons.
Confusing rootstock shoots with main canopy. A homeowner who doesn’t know about the graft sees the rootstock shoots as part of the tree and prunes them as such — reducing them lightly but never removing or strongly subordinating them. The rootstock keeps winning.
Not pruning at all. The most common outcome. The Weeping Cherry that started as a beautiful umbrella becomes an awkward upright cherry tree with a small weeping appendage hanging off one side, over a 10–15 year period of unchecked rootstock dominance.
Weeping Cherries are one example of a much broader principle in ornamental arboriculture: most named cultivars on residential properties are grafted. Japanese Maples. Many flowering crabs. Tree-form lilacs. Many ornamental pears. Each of them has a graft union somewhere on the trunk, and each of them can produce rootstock shoots that compromise the cultivar above the graft if not managed.
If you have ornamental trees on your property, knowing where the graft union is — and what the rootstock shoots look like — is one of the more useful pieces of arboriculture knowledge a homeowner can carry. It’s the difference between maintaining the cultivar you paid for at the nursery and gradually losing it to its own rootstock.
For inspection and cultivar-preserving pruning on grafted ornamentals, request a consulting arborist visit →
