Hosta care guide: when & how to prune, fertilize and spray

When: from the last spring frost to 3 weeks after.

• zones 3–5: about May 10–31
• zones 6–7: about Apr 15 – May 6
• zones 8–10: about Feb 25 – Mar 18

A single feeding as new shoots emerge is enough for most perennials. Overfeeding makes them floppy.

1. Scatter a balanced slow-release or organic fertilizer around the plant, or top-dress with 1 in (2–3 cm) of compost, then water.

What to use: 🌿 Balanced organic granular fertilizer (e.g. Espoma Plant-tone 5-3-3) · 🌿 Finished compost or composted manure

When: from 1 week before to 2 weeks after the last spring frost, then every 3 weeks (3 times a season).

• zones 3–5: about May 3–24
• zones 6–7: about Apr 8–29
• zones 8–10: about Feb 18 – Mar 11

Treating as shoots emerge stops slug populations before they build up.

1. Scatter iron phosphate bait lightly around the plants (it's safe around pets) and reapply after heavy rain.

What to use: 🌿 Iron phosphate slug bait (e.g. Sluggo)

When: 2–6 weeks after the last spring frost.

• zones 3–5: about May 24 – Jun 21
• zones 6–7: about Apr 29 – May 27
• zones 8–10: about Mar 11 – Apr 8

Mulch keeps roots cool and moist, suppresses weeds and slowly feeds the soil. Applying it after the soil warms lets roots wake up first.

1. Spread 2–3 in (5–7 cm) of mulch over the root zone.
2. Keep mulch 2–3 in (5–7 cm) away from stems and trunks. Mulch piled against bark invites rot and rodents.
3. Don't go deeper than 3 in (7 cm) in total. Too much mulch suffocates roots.

What to use: 🌿 Shredded hardwood or pine bark mulch

When: from the first fall frost to 4 weeks after.

• zones 3–5: about Oct 1–29
• zones 6–7: about Oct 25 – Nov 22
• zones 8–10: about Dec 1–29

Spores of slug eggs and leaf diseases (hosta leaves turn to mush after frost) overwinter on fallen leaves and splash back up in spring. Removing them is the single best way to prevent next year's outbreak.

1. Rake up and remove fallen leaves and dropped fruit from under the plant.
2. Bag diseased material or put it in the trash. Don't compost it unless your pile gets hot (140°F/60°C+).
3. Cut out any dead or obviously diseased twigs you can see.

Tools: Rake, Bypass pruners

When: from 1 week before to 3 weeks after the last spring frost.

• zones 3–5: about May 3–31
• zones 6–7: about Apr 8 – May 6
• zones 8–10: about Feb 18 – Mar 18

Spring division, as the shoots poke up, is easiest and does the least damage.

1. Only needed if the clump is crowded, flowering less, or dead in the center.
2. Dig around the clump and lift it with a fork.
3. Split it into fist-sized pieces with a sharp spade or knife, each with roots and shoots.
4. Replant at the same depth, water well, and share the extras.

Tools: Spade, Garden fork