Healthy Redbuds died.
We we have had two very nice redbud trees for about ten years. They are located near each other (about 12 feet apart). Last year they flowered spectacularly. Last year started wet and later when the drought set in we made sure the redbuds had adequate water. The foliage seemed fine going into fall and the leaves dropped normally. This spring neither tree flowered or leafed out. There are tiny dark colored buds that are only 1/16 to 1/8 inch in size. They don't seem to change and we assume both trees are dead. We are baffled by this loss.
Polk County Iowa
The very cold temperatures this past winter likely killed the redbud trees.
Redbuds are native from southern Iowa to northern Louisiana. Redbuds are typically grown from seeds. Plants grown from seeds collected in southern Missouri or Arkansas are not as cold hardy as those grown from seeds collected in Iowa or northern Missouri.
When purchasing a redbud, its important to obtain a tree grown from a northern seed source. When visiting garden centers and nurseries, inquiry about the source of the redbuds. Reputable garden centers in Iowa sell only redbuds grown from northern seed sources.
I have noticed a number of dead redbuds in central Iowa. Most of the dead redbuds are 5 to 10 years old. Most of the larger, older redbuds are fine. This past winter was the first very cold winter for redbuds planted in the last 5 to 10 years. Some of the marginally hardy trees did not survive. The larger, older trees survived this past winter as they had experienced similar temperatures at some point in their lives.