Your Seasonal To-Do List
WaterOn average, hostas require 1" of water per week, whether by rainfall or irrigation. However, do not water hostas in the Spring until the threat of frost has passed to prevent root rot.
SoilHostas are known for their ability to grow in just about any soil. However, rich, slightly acidic, well-draining soil will keep your hostas looking their best.
FertilizerAs the hostas emerge in the Spring, apply a 10-10-10 balanced fertilizer (preferably granular slow-release) around the emerging clumps.
ProtectionDon't uncover your hostas too early!
Protect ones that have already emerged from any late Spring freezes by covering them with blankets, sheets, plastic and the like. Late frosts can do significant damage. Plants that freeze and thaw and refreeze and rethaw are the most likely to show problems later.
DivisionDivision is possible now if the ground is workable. However, this is not the best time since the roots will not grow until after the leaves form. The best time is late summer. See our separate website article on dividing hostas for more information.
TransplantingLate Spring is a good time to transplant an entire hosta plant.
Other Care Tips for the Spring
- When all danger of frost has passed, rake the mulch that you mounded up over the hosta as winter protection away from the developing eyes to prevent crown rot.
- Apply some fresh mulch away from the center crown.
- Disinfect all hardscapes with a solution of 10% ammonia to water to kill slug eggs.
- A sprinkling of clean crushed egg shells will deter grubs and give the hosta some added calcium.
WaterBe careful not to water too much now. Drier is better since there are still some pretty cold days and nights ahead.
FertilizerAs hostas emerge in Spring, apply a slow-release balanced fertilizer. Other gardeners prefer to fertilize pot-grown perennials with a diluted fertilizer (25% strength) every few weeks instead.
CareIf you've stored your potted hostas in an unheated garage or shed, slowly begin to acclimate the hostas to outside temperatures as it warms.
WaterLack of sufficient water during a dry summer can cause the hosta to go into mid season dormancy where the outer leaves will fade and wither. By keeping the hostas well watered through the summer, especially during the hottest parts, you can help to avoid the hosta looking ragged, affectionately called "The Summer Uglies" by keeping the roots moist. Water deeply and more often. Hosta roots should receive at least 1" of moisture per week for healthy growth.
FertilizerIn early summer, give the hostas a second (and last) feeding of a balanced 10-10-10 fertilizer. Some gardeners prefer a fertilizer with a little more nitrogen at this time. Hostas can be fertilized through the early summer, but be sure to stop two months before your expected first frost date to allow the hosta to slowly settle into its winter dormancy.
DivisionIt is possible to divide your hosta in the summer provided you keep the hosta divisions well watered until established. Late summer, after the heat of the summer has passed, is the best time to divide hostas. August is usually the perfect time and will give your hosta divisions six weeks before the first frost to establish new roots in their new home.
Other Care Tips for the Summer
WaterWater every other day as needed if no rain and let soak through. This is not only to hydrate the hosta plant, but will help to flush out the salts that tend to develop in potted soil.
FertilizeHostas generally will not need fertilizer during the summer if adequately fertilized in the spring.
Other Care Tips for the Summer
Move the container to a shadier spot in the garden during the hottest part of the summer to reduce plant stress or use some man-made shade to give the hosta a respite from the summer's heat.
WaterOnly water when the foliage is still green and it hasn't rained for about two weeks.
DividingStop dividing any hostas six weeks before your average first frost date. For most of the U.S., this is September 1.
ProtectionTime to prepare your hostas for their winter sleep.
Cover newly-planted hostas with an extra layer of leaves or mulch for their first winter protection. Be careful not to over mulch which can actually smother the plant. The best mulches are leaves, straw and other biodegradeable materials which are light and allow for air pockets.
Other Care Tips for Fall
Since slugs produce eggs in the Fall, this is a good time to apply a slug killer. For more detailed information about slugs in the garden, see our separately website article.
As the greenery dies back in the Fall, you have one of two choices:
1. Leave it be. The dead foliage does provide an extra layer of mulch so many gardeners feel that removing the dead foliage is unnecessary.
2. Remove your dead foliage before the first frost and discard. (Do not compost.) This will help remove nematodes, slugs and any diseased leaves. First disinfect the scissors or knife you're using between cuttings with a solution of 10% bleach 90% water.
WaterHostas in pots that are stored in an unheated space for the winter could dry out competely. Check pots once a month and add a little water if it is very dry. The most important time to check on the soil is right after you've stored them until the hard frosts hit, and then in early Spring as it warms up. Once it's the dead of winter, no care is needed. Do not water over frozen soil.
ProtectionThere are several ways to protect your hostas in pots over the Winter months: The key is to keep the hostas away from overhead moisture and to protect them from sudden swings in temperature.
There are several ways to do this:
- Move them to an unheated garage or shed.
- Bury the entire pot or group of pots in the ground or cover the group with leaves.
- Large potted hostas will normally overwinter well in place with an additional layer of mulch on top of the soil. They can be huddled together out of direct sun.
- After the soil is nearly frozen, you can tip the pots over on their sides to give them extra protection from overhead moisture.
- More labor intensive, but if you have a prized hosta in a pot, you can plant it in the ground and repot it again the next Spring.
With hostas, there is no growth during dormancy as there might be with other perennials.
Water and FertilizerNone.
Don't worry about the snow -- It's a great insulator!
ProtectionHostas don't need anything during their dormancy except protection.
Hopefully you've already protected them in the Fall. If not, protect them now!
Check monthly the soil in the potted hostas that are stored in an unheated garage or shed. Only water if completely dry to the point of being dusty.
Never water frozen soil. At this time, drier is better than wetter.
Where to go next!