Basic discussion is below. For more information try our FAQ pages.
The care of your new hosta plant is fairly simple. If you have a choice of where you plant your hosta, select a soil that is loose and well drained. The soil should be amended with compost to a depth of 12–18 inches. Place the hosta in the hole so that the plant crown is level with the ground. Not too deep! Place some good soil around the roots and water thoroughly. Space the plants to allow room for them to grow, based on the size of the cultivar. Hostas do best when left undisturbed for several years. After they are planted, your hostas will require very little care. Hostas are best grown under trees for providing the shade that hostas prefer. Because the tree roots will compete for moisture, make sure that your plants get enough water during the growing season. A layer of mulch will help reduce water loss, keep the roots at an even temperature, and prevent competition from weeds. Although it is not necessary, an annual feeding of slow release fertilizer will keep your hostas happy.
Hostas can be planted (and divided) at any time during the growing season, although most people try to plant hostas in the spring. The later in the season, the more important it is to keep the plant adequately watered. You may need to provide temporary protection from sun after you divide them. If planting or dividing in the late summer or fall, give the hosta time to settle in before the ground freezes (in most zones, that means stop planting in mid to late September).
Sun vs. shade
There has been a great deal of debate over where particular hostas will do best. Pick out a shady spot that is protected from hot afternoon sun. The most common mistake made by newbies (new hosta lovers) is thinking that all hostas do best in full shade. This is not the case. Hostas are shade tolerant, which means that they will do well in varying degrees of shade, yet still like some sun. On the other hand, they are not sun-lovers: in their native habitats they grow on hillsides or in meadows where they are shaded by trees or taller plants. If possible, try to avoid full afternoon sun. Some hostas, such as H. plantaginea, will tolerate sunnier conditions. Frequent watering will help a hosta survive more direct sunlight than it normally would tolerate. And remember that "sun" in Georgia is not the same as "sun" in Minnesota! The recommendations here are for the mid-Atlantic region.
Fertilizer and mulch
If you feel it is necessary to apply fertilizer, most professional hosta growers prefer an annual application of 10-10-10. For those who tend toward organic gardening, there are several products that have worked well for hosta gardeners. Some use Milorganite, which has deer-repellent properties; others choose animal manure. Another organic fertilizer with 8% nitrogen is soybean meal.
What about using mulch? Some people simply weed the areas until the hostas come up in the spring and the hosta itself prevents the further development of weeds. Other people use pine straw or cocoa mulch, as they both tend to diminish slug problems and do not break down as quickly as other mulches. Still others find that double shredded hardwood mulch works best because of its water retention capabilities. Shredded leaves can increase the slug and vole problems, so consider that before choosing this mulch. Regardless of the type of mulch you choose to use, do not mulch deeper than 2–3 inches, and avoid burying the crown of the plant. In many cases over-mulching has led to vole problems by providing a nice warm medium that is easy to tunnel through.
Hostas love plenty of water. In their native habitat hostas receive over 60 inches of rainfall annually. In most of the United States this is well above normal rainfall levels. Therefore, it is essential to supplement nature to ensure that the plant receives a minimum of 1 inch per week during the growing season. People who have achieved maximum growth conditions provide 1.5 inches per week, or 0.5 inch every 3 days. Due to their leaf size, hostas have a very high transpiration rate so soil conditions should allow for optimum water retention.
Hostas in containers
Are you interested in growing hostas in pots, or creating a miniature garden of mini hostas? Visit our page here.
Hostas from seeds (hybridizing)
Are you interested in growing hostas from seeds? The most important thing to know is that most hostas are hybrids, and therefore do not come true from seed. Notably, variegated hostas rarely give variegated offspring! For that you need an unstable streaked-variegation parent, whose instability passes on to the seedlings which can then "settle out" to a typical variegated pattern. Still, it can be fun to grow hostas from seeds, even if you only expect single-color progeny. See our FAQ page for an introduction to hybridizing and growing from seed, or David Teager's three-part video series (Part 1). There is a great tutorial on hybridizing and growing hostas from seed by Joshua Spece at In the Country Gardens and Gifts.
Challenges: tree roots, pests, and diseases
A few brief comments are below, but also see our FAQ pages.
Hostas have trouble competing with shallow roots from trees and shrubs; in our area red and silver maples pose the greatest threat. Where there are limited planting areas and you want to keep the trees, plant the hosta in a container or nursery pot large enough to accommodate growth. This container planting also has been recommended in cases where voles (see below) are an extreme hosta "predator." If you use a container you need to keep the holes in the bottom open to ensure good drainage.
Hostas tend to be pest free. However, slugs do tend to enjoy eating holes in the leaves of hostas and the slug is considered by many to be the number one pest of hostas. Of course, deer don't eat little holes, they eat entire leaves! And voles burrow shallow tunnels to eat the roots and crowns of your hostas, and can cause hosta devastation in a short time.
The next most significant problems that occur on occasion are fungal diseases. In the spring (or due to winter moisture), plants may fail from crown rot, with rotten-smelling, mushy crowns evident when you dig them up (caused by a variety of fungi). In warmer climates, in particular, southern stem blight may become a problem in the summer when the extreme heat, humidity, and moisture cause the petioles (stem bases) to rot so that the leaves fall off the plant. The fungus (Sclerotium rolfsii) will show as orange-brown nodules at the base of the petioles. A strong fungicide (or even bleach solution) is the best treatment, along with preventing moisture from sitting on the crown of the plant. Having mulch on the crown of the hosta can contribute to the problem. Do an internet search for more information on treatment.
Foliar nematodes are a problem that is becoming more widespread every year. In cases of nematode attack, the microscopic worm feeds on the leaf tissues between the veins of mature leaves, causing unsightly brown streaks on the leaves in summer, and eventual weakening of the plant. Treatment with very hot water is effective, but difficult; new research has shown that properly timed treatments with a product called NemaStop may be as effective, and much easier (but costlier). Be sure not to share any infected plants, as the nematodes travel easily from plant to plant within droplets of water (rain).
A significant concern among hosta growers is Hosta Virus X (HVX), which appeared in commercially grown plants and has infected home gardens. The virus, identified over 25 years ago, is spread by infected sap (plant fluids), either by contaminated water (in commercial propagation) or by contaminated garden tools, via wound-to-wound transfer. The virus causes discoloration of the leaves (usually dark green blotches in the veins of blue and gold hostas), with eventual deformation of the leaf and weakening of the plant. Concerned gardeners should quarantine suspicious plants, and sterilize garden tools by removing sap from tools between contact with individual plants (perhaps with a disinfectant wipe). Visit our FAQ page or here for a nice summary, or here for even more information.