To plant hostas, start by mixing organic matter such as compost or rotted manure into the existing soil. Then dig a wide, shallow planting hole that’s about twice as wide as the potted hosta from the nursery (or the bare root hosta), but no deeper than the soil in the planting pot.
Pull the root ball out of the pot. If the hosta is rootbound, loosen it up and pull out any thick white roots circling the bottom. Place the hosta in the hole and backfill carefully, ensuring the soil around the base is at the same level as the surrounding soil. Water thoroughly after planting.
How to plant hostas
Planting hostas is easy as long as you take the time to understand how hostas grow best. In general, select a good planting location, prepare the soil properly, and place the plant at the right elevation. Hostas are best planted in spring or fall, although they can be planted any time of year as long as the soil is not frozen and the plants have ample water.
Look for a partial shade location, ideally with dappled sun in the morning and shade in the afternoon (particularly in hot climates). Hosta plants tend to do best without too much harsh direct sunlight.
Here are detailed steps for how to plant hostas.
1. Prepare the soil
Start by working some organic matter such as compost, peat moss, coco coir, or rotted manure into the planting area. This will help improve drainage and add nutrients to the soil. If you’re working with clay soil, you may also wish to add some coarse, gritty material like sand or perlite to the soil, as these materials improve drainage.
Research the mature size of the hosta variety you’re planting. You want to prepare all the soil inside the future footprint of the plant. The roots will usually extend even farther than the aboveground footprint of the mature hosta. So, if you’re planting a hosta that’s expected to grow to a spread of 36″ wide, prepare the soil in at least a 36″ diameter circle at the planting location. Mix the organic material and sand into about the top 8″-18″ of soil (depending upon the size of the variety) if possible.
2. Dig a wide, shallow hole
Next, dig a wide, shallow planting hole. For hostas sold in plastic nursery pots, a planting hole that’s twice as wide as the pot is usually sufficient. Don’t dig the hole any deeper than the soil inside the planter pot. The planted hosta should not have extra soil up the base of the stems. It should be planted in the ground at the same depth it’s planted in the pot.
If planting bare-root hostas, dig a wide, shallow hole that is at least wide enough to hold all the roots without them being bent or folded. The central crown of the plant (where all the roots meet) will be placed up close to the soil level.
3. Place the plant in the hole
Place the hosta plant in the hole. For potted hostas, carefully pull the plastic nursery pot off of the root ball. If the hosta is rootbound, loosen the roots up a bit by gently pulling them apart. You may also need to cut through any very thick white roots circling the bottom of the root ball with a sharp knife. Try to straighten out and untangle roots before placing the plant in the hole.
For bare root hostas, hold the plant in the hole so that the crown area in the middle of the roots is close to the soil level surrounding the hole. You may have to prop up the crown with a bit of a soil mound on the bottom of the hole. Arrange the roots in an outward direction, ideally pointing downward as they rest on the sides of the mound.
4. Backfill the hole
Carefully backfill the planting hole with soil, taking care not to bury the plant’s central crown any deeper than it was growing in its pot or bare root state.
5. Water thoroughly
Water the hosta thoroughly after planting. Deep watering will help the soil settle around the roots of the plant. If the soil settlement is significant, you can top up the soil around the base (as long as the plant’s base isn’t buried any deeper than it was in the planter). Also, try to gently knock off any dirt from the foliage.
5. Mulch around the base
After planting, add a layer of mulch around the base of the plant. This will help the soil retain moisture, stay cool in the hot sun, and suppress weeds. A layer of 2″-3″ of organic mulch, such as wood chips, organic compost, leaf mold, cocoa shells, pine needles, or shredded leaves, is ideal.
Caring for hostas after planting
Hostas must be watered regularly in the weeks and months immediately following planting. They will need deep watering at least once a week during dry weather and possibly more during a heat wave. Check the soil around the plants to make sure it’s not drying out. If the soil is dry an inch or two below the surface, it’s time to water.
Watering can be reduced somewhat after the plants become established, but they will always need regular watering to thrive during extended droughts. Hostas are native to an area with high rainfall that is uncommon in many climates where they are cultivated as garden ornamental.
Always water the roots of the hosta rather than water the leaves from overhead. You can do this with a watering wand or, most easily, with a drip irrigation system. Set the drip irrigation system to water in the early morning, as late-night watering tends to attract the slugs and snails that love to feast on hosta foliage. You can also fertilize the newly planted hosta in spring and early summer (but avoid autumn feedings).