Ornamental · Asparagaceae
Hosta
Hosta
Give it shade, steady moisture, and rich soil, and the hosta carpets the ground in bold leaves year after year.
Partial shade
Every 3–7 days
USDA 3–9
0–3 ft · 0.1–0.9 m
Overview
Hostas are the workhorse of the shade garden, grown more for their leaves than their flowers. They come up every spring as tight spears, then unfurl into broad mounds of foliage in greens, blues, golds, and crisp white-edged patterns. As tough, long-lived perennials, they settle in across a wide stretch of the country and ask for very little once established.
The range of size is striking. A miniature can stay just 4 inches (10 cm) tall while a giant spreads to 4 feet (122 cm) across, so there's a hosta for the front edge of a bed and one to fill a whole shady corner. They send up tall scapes of pale, sometimes fragrant flowers in summer, but most gardeners grow them for the bold, layered leaves that hold the show all season.
Their one real demand is shade and steady moisture. Give them rich, damp soil out of harsh afternoon sun and they thrive for years with almost no fuss. The two things that test a grower are slugs, which chew the leaves ragged, and a crown that rots if the soil stays soggy.
Care
The short version: filtered or dappled shade, rich soil kept evenly moist with about an inch of water a week, and a mulch to lock that moisture in while keeping it clear of the crown.
Light
Hostas want filtered or dappled shade rather than full sun or pitch dark. Gold and yellow types take a little morning sun to bring out their color, while blue-leaved kinds need the deepest shade to hold their hue and dodge scorch.
Water
Aim for about an inch of water a week, given deep and even, with the soil kept moist but never soggy. A 2 to 4 inch (5 to 10 cm) mulch layer holds that moisture in and saves you watering through dry spells.
Soil
Plant in rich, well-drained soil loaded with organic matter, since hostas are heavy feeders of moisture and nutrients. A pH anywhere from 6.0 to 7.5 suits them, so most garden ground works once you've worked in some compost.
Humidity
Ordinary outdoor air is plenty, so there's no number to hit. What matters more is airflow around crowded clumps, which keeps the foliage drier and slows the pests and rots that thrive in stale, damp corners.
Feeding
A balanced garden fertilizer in spring as the leaves emerge covers most hostas, and only if a soil test says they need it. Stop feeding by late July so the plant can harden off and hold its winter hardiness.
Pruning
Cut the spent flower scapes off once the blooms fade, and trim yellowed foliage back in late fall or early spring. Clearing away dead leaves does double duty by removing the damp cover slugs hide under.
Size & spacing
Mature plants range from 4 to 36 inches (10 to 91 cm) tall and spread 6 to 48 inches (15 to 122 cm) wide depending on the type. Match the spacing to the variety's eventual width so the mounds can fill in without crowding.
When to plant
Hostas are hardy perennials that come back on their own, so timing is about getting them in the ground, not chasing a harvest. Set new plants out in spring once the soil warms and the growing tips show, or in early fall, and look for the flower scapes to rise above the leaves through summer.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Seed is not recommended as cultivars do not come true; not typically started indoors
- Plant: Spring after the soil warms and growing tips emerge, or early fall
- Harvest: Flowers in summer on tall scapes above the foliage
Hardiness
USDA hardiness zones: 3–9
Temperature: down to -40°C
Troubleshooting
Most hosta trouble shows on the leaves, whether it's something chewing them or the weather scorching them. A few problems run deeper and reach the crown. Match what you see below and step in before a minor blemish turns into a lost plant.
Wilting plant with yellow leaves and a soft, rotting crown
A mushy, discolored crown points to crown and root rot, which sets in when the base stays too wet or sits buried under piled mulch. It follows soggy ground and heavy mulch pressed against the stem. Rake the excess mulch away in spring, fix the drainage, and dig out any plant that's already collapsing, since there's no saving a rotted crown.
Fix:
- Remove excess mulch from around the crown in spring
- Improve drainage
- Remove and destroy badly affected plants
Angular brown streaks trapped between the leaf veins
These vein-bounded streaks are the signature of foliar nematodes, microscopic worms that move through wet foliage. The dead tissue stops sharply at each vein, which gives the leaf its banded, wedge-shaped look by mid to late season. Strip off and destroy infested leaves, water at the base so you don't carry the pest from leaf to leaf, and pull out any plant that's badly riddled.
Fix:
- Remove and destroy infested leaves
- Avoid overhead watering that spreads nematodes
- Remove and discard severely infested plants
Ragged holes chewed in the lower leaves with slime trails
This is the work of slugs and snails, which feed after dark and leave silvery trails behind them. Pick them off by hand at night and drop them in soapy water, set a few traps to clear each morning, and ring vulnerable plants with copper. Pulling mulch back from the crown takes away the damp hiding spots they depend on.
Fix:
- Hand-pick at night and drown in soapy water
- Set traps and remove slugs each morning
- Use copper barriers to deter slugs
- Pull mulch back from the crown
Brown, scorched patches on the most exposed leaves
This is sunscald, and it shows up where too much direct sun or too little water dries the leaves out. The worst damage lands on the leaves facing the sun during hot, dry spells. Move the plant into deeper shade, water more through heat, and mulch to hold moisture in the soil. Blue-leaved types in particular want a shadier spot.
Fix:
- Move or transplant the hosta to a shadier location
- Increase watering during heat
- Mulch to retain soil moisture
Toxicity
Hostas are toxic to animals. Every part holds a natural compound called saponins, and the ASPCA lists the plant as poisonous to cats, dogs, and horses. People come to no harm growing or handling it, but the leaves and trimmings should be kept well away from pets and grazing animals.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat that nibbles the leaves usually drools and then vomits, with loose stools and a flat, listless mood to follow.
Dogs Mild
Expect an upset stomach in dogs, so vomiting and diarrhea, along with a noticeable dip in energy after they chew on the foliage.
Horses Mild
Grazing horses react to the saponins with stomach upset, loose droppings, and a dull, depressed manner.
Rabbits Toxic
The same saponins make the leaves a poor choice for rabbits, bringing on digestive upset and sluggishness, so keep them out of reach.
Livestock Toxic
Goats, sheep, and cattle that browse the foliage can suffer digestive distress from the saponins and are best fenced away from plantings.
Birds Caution
There's little to suggest birds enjoy hosta, but the saponins in every part mean it's safest to keep curious pet birds from picking at it.
People Low
No part of the plant is eaten, yet the saponins make it a poor idea to chew on. People come to no harm handling it, so the real caution is keeping pets and grazing animals from the leaves.
No special skin handling precautions are required for people, but keep plants and trimmings away from pets and grazing animals.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Hostas number in the thousands, but a few classics turn up again and again for their size, color, or markings. These are the ones worth knowing by name.
Sum and Substance
One of the largest hostas going, with huge chartreuse-gold leaves that take more sun than most.
Halcyon
Heart-shaped blue-gray leaves that hold their color best when given deeper shade.
Blue Mouse Ears
A miniature whose thick, rounded blue-green leaves really do look like little mouse ears.
Patriot
Dark green leaves edged with wide, crisp white margins for sharp contrast in the shade.
How to propagate
Hostas are easy to multiply, and there's only one reliable way to do it: lift a mature clump and split it into new plants.
DivisionEasy
Early spring as the eyes or growing tips emerge (can also divide in early fall) · One to two growing seasons to fill back in
Division is the standard way to make more hostas, and the moment to do it is early spring as the eyes push up, though early fall works too. Lift the whole clump and cut it into sections, making sure each piece carries growing tips and a share of roots, then replant at the original depth and water it in well. Give the new divisions one to two growing seasons to fill back out into full clumps.
Myths
Hostas need full shade and will not grow where any sun reaches them.
Most hostas are happiest in filtered or dappled shade, not pitch dark. Gold and yellow types actually want 2 to 3 hours of morning sun to color up, and only the blue-leaved kinds truly need the deepest shade.
Hostas are completely harmless to pets.
Every part of a hosta holds saponins, and the ASPCA lists the plant as toxic to cats, dogs, and horses. A pet that eats some can end up vomiting, with diarrhea and a low, depressed mood.