How to Winterize Hosta Plants
- 1). Stop regular fertilizer treatments in late summer, at the end of July or in early August. This prevents the hosta from putting on new growth that may be killed or damaged by winter freezes.
- 2). Trim off any damaged leaves or those leaves suffering from disease or insect infestation prior to the first fall frost. Trim the leaves off with clean shears near where they emerge from the plant. This prevents the leaves from harboring diseases over winter when the hosta is weakened by cold.
- 3). Apply a 3-inch layer of mulch around and over the hosta after the ground freezes in fall. Place the mulch on top the crown of the plant, which is the area where the leaves emerge from the roots, to protect it from cold. This mulch prevents the ground from heaving during winter thaws and protects the base of the plant from winter burn from cold winds.
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