To prepare hostas for winter, keep watering them through fall whenever the soil turns dry. Wait for a hard frost to kill the leaves. Then cut the leaves and stems off at the base. Take the dead leaves out of the garden bed. Hostas that have grown in the ground for a full season need no winter cover. Hostas planted in late summer or early fall need a few inches of straw or pine needles once the ground freezes. Pull that mulch back in early spring before new shoots appear.
Is your hosta new this year? Plan to mulch it. Has it grown in that spot for at least one full season? Skip the mulch and focus on cleanup. Is it in a pot? Go to the section on potted hostas below. Pots need different care.
How to prepare hostas for winter
Hostas are hardy perennials. NC State Extension lists them for USDA zones 3 to 9. The leaves die back once the temperature drops to 28°F (-2°C) or below. To winterize a hosta plant in your landscape, give it enough water through fall, clean up the dead leaves, and mulch the plants that need it.
1. Water your hostas through fall and winter
Watering is the first step of fall care. Give hostas a deep soak whenever the fall weather turns dry. Keep going after the leaves die back. Illinois Extension notes that roots keep taking up water after the top growth goes dormant.
Dormancy does not mean the watering stops. It means you water less. Colorado State University Extension recommends winter watering during long dry spells with no snow cover, about once or twice a month. Water only when the air and soil are above 40°F (4°C). Water at midday so it soaks in before it can freeze at night. Skip the watering when rain or snow keeps the soil moist. NC State Extension notes that hostas do not tolerate soggy soil, above all in winter.
2. Cut back the dead leaves
Wait for a hard frost to kill the leaves. Then trim off the dead leaves and stems at the base with clean pruners. Iowa State University Extension says hostas and most other perennials can be cut back in November after a hard freeze. Bag the leaves and take them out of the bed.
Fall cleanup helps hostas in two ways. Illinois Extension says cutting back the foliage reduces next year’s slug population. It also removes leaves carrying hosta nematodes or leaf diseases. Throw diseased leaves away so the problem does not spread in spring. Pull soggy tree leaves off the hosta crown as well. Wet leaves on the crown draw slugs, rabbits, and voles.
Prefer a natural look in winter? Iowa State notes that the cleanup can wait until early spring.
3. Mulch new hostas after the ground freezes
Most hostas do not need winter protection if they have been in the ground for at least one full growing season, according to Iowa State University Extension. Hostas planted in late summer or early fall are different. Repeated freezing and thawing of the soil can heave them out of the ground.
Cover these plants with several inches of clean straw or pine needles after the ground freezes. Iowa State times this for mid to late November in Iowa. The mulch keeps the soil frozen, so it does not freeze and thaw over and over. University of Nebraska-Lincoln Extension says to remove the hosta foliage before the mulch goes on. Pull the mulch back in early spring before new growth shows. Illinois Extension warns that mulch left on in spring can rot the crown.
When to prepare hostas for winter in your zone
Frost sets the timing, not a date on the calendar. Hosta leaves die back at 28°F (-2°C) or colder, according to NC State Extension. That happens at different times across the hosta’s range of USDA zones 3 to 9. Check your growing zone first, then watch your local weather.
In zones 3 to 5, do the cleanup in the weeks after the first hard freeze. In Iowa, Iowa State cuts back hostas in November and mulches late-planted hostas in mid to late November. Water any dry spells in fall before the ground freezes.
In zones 6 and 7, the steps stay the same. Time them to your own first hard freeze.
In zones 8 and 9, hosta leaves may hang on into winter. NC State Extension says the foliage dies back in late fall or winter. Hostas also need a dormant period of a couple of months below 40°F (4°C). Let the leaves die back on their own. Then cut them off and clean up the bed.
How to overwinter hostas in pots
A hosta in a pot has less soil around its roots than a hosta in the ground. The pot can freeze and thaw over and over. Illinois Extension gives three ways to protect hardy perennials in pots:
- Sink the pot into the ground up to the rim. The soil around it insulates the roots. Mulch over the top. Lift the pot out in spring once the danger of a hard frost has passed.
- Move the pot into an unheated garage, shed, or cold basement. Keep it between 20°F and 45°F (-7°C and 7°C). Hostas need that cold to go dormant.
- Group the pots in a sheltered spot, such as the north or east side of a building, out of strong wind and sun. Cover them with a thick layer of straw, leaves, or wood mulch. Remove the mulch when growth starts in spring.
Water the pots well before winter. Moist potting mix freezes at a slower rate than dry mix. Check stored pots during winter. Ask Extension advises keeping the soil from drying out all the way, but not keeping it wet, since wet roots can rot.
Tips for helping hostas survive cold winters
Fall cleanup is part of the same job across the garden. The steps for hostas match the way you winterize perennials in other beds. Two more steps help hostas through the winter.
Divide hostas at the right time
NC State Extension suggests you divide hostas every 3 to 5 years, in early spring as the leaves come up. Some gardeners divide in fall instead. See when to divide hostas for the timing in each season. A fall division has a small root system, like a newly planted hosta. Mulch it after the ground freezes so frost does not heave it out.
Watch for voles
Illinois Extension lists voles as a winter pest of hostas. The options it names are changes to the garden, repellents, and trapping.
If you want to add more hostas, Nature Hills sells dozens of varieties.
Tools for preparing hostas for winter
Five tools cover the job, from fall watering to slug control. As an Amazon Associate I earn from qualifying purchases.
Watering wand
Hostas need deep watering through the fall. The GREEN MOUNT watering wand is 24 inches long, so the water reaches the soil under the leaves. Its shower head has 661 small holes for a soft spray.
Bypass pruners
Dead hosta leaves get cut off near the ground after the first hard frost. The Fiskars bypass pruning shears (also at The Home Depot) cut stems up to 5/8 inch thick. A lock holds the blades closed between uses.
Garden bag
Cut hosta leaves need to leave the garden bed, since they shelter slugs. The Fiskars Kangaroo garden bag (also at Target) holds 30 gallons and pops open by itself. It folds down to 3 inches for storage.
Digging fork
A digging fork lifts a hosta clump out of the ground for dividing. The Spear & Jackson stainless steel digging fork (also at Target) has stainless steel tines that resist rust.
Slug bait
Slugs and snails are drawn to hostas. Monterey Sluggo is a granular slug and snail bait made with iron phosphate. It is OMRI Listed for organic gardening. Follow the label directions.
Hosta winter care FAQ
Should I cut back hostas in fall or leave them?
Either works. Iowa State says hostas can be cut back in November after a hard freeze, or cleaned up in early spring. Fall cleanup has two benefits. Illinois Extension says it cuts down next year’s slugs and removes diseased leaves and nematodes.
When should I cut back hostas?
Cut them back after a hard frost kills the leaves. NC State Extension says hosta foliage dies back at 28°F (-2°C) or below. In Iowa, that cleanup falls in November. Cut the leaves and stems at the base and bag them. For more detail, see when to cut back hostas.
Do hostas need mulch in winter?
Established hostas do not. Iowa State says hostas in the ground for at least one full growing season need no winter protection. Mulch hostas planted in late summer or early fall, after the ground freezes. Use several inches of clean straw or pine needles. Remove it in early spring before new growth appears.
Do hostas need water in winter?
They need it in dry winters with no snow cover. Colorado State University Extension suggests watering once or twice a month during dry spells, when the air and soil are above 40°F (4°C). Skip it when rain or snow keeps the soil moist. Hostas do not tolerate soggy soil in winter.
Can hostas stay outside in pots over winter?
Yes, with protection. Sink the pot in the ground up to the rim, or group pots in a sheltered spot and cover them with a thick layer of mulch. Illinois Extension lists both, along with storage in an unheated garage or shed.
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