Purple Robe Locust Suckers Produce Black Locust, Not Purple Robe

Grafted Tree Suckers Revert to Rootstock

A Modoc County gardener wants to propagate Purple Robe locust from root suckers. Purple Robe is a cultivar grafted onto black locust rootstock.

Why Suckers Won't Work

Suckers arise from the rootstock (black locust), not the scion (Purple Robe). Any tree grown from them will be plain black locust—thorny, white-flowered, not the purple-flowered cultivar.

Propagation Options

• Root cuttings: From scion roots (if accessible) — difficult.
• Grafting: Scion wood onto black locust seedlings — professional method.
• Buy new: Named cultivar from nursery — guaranteed true-to-type.

Sucker Management

Remove suckers promptly—they divert energy from the grafted top and create thorny thickets.