Hostas are the number one selling plant in North America. 

Hosta Leaves

Just exactly what is it about these perennials that attract so many gardeners?  Certainly the lists of benefits include: beauty, hardiness (Zone 2 – 10), longevity, and durability.

Hosta leaves come in four main colors: blue, green, yellow, and white.  Color combinations are also important.  The leaves can have different shapes as well as margin colors different from the center color.  The leaves can have wide irregular margins or very distinct but thin margins.  The spring color also may not be stable all season long.  The leaf surface can be flat, curled, cupped, wavy, contorted, piecrust, or furrowed.  Flat surfaces have even and smooth features.  A rugose leaf has uneven features such as dimpled, puckered, embossed, ruffled, pleated, wrinkled, and crinkled leaf surfaces.  Cupped leaf surfaces are cupped around the margins.  Wavy leaves are relatively smooth but wave or undulate along the margins.  Contorted leaves are warped, or distorted.  Piecrust leaves have closely spaced, distinct, regular, undulations along the margins.  Furrowed leaves show the veins sunken or impressed, creating a ribbed effect.

Hosta Flower

The Hosta flower seems to be a second aspect of the Hosta. Hostas can bloom anytime from June to October and the flowers can be funnel or bell shaped.  Many look like lilies and some don’t open at all.  Some are fragrant and most are purple, white, or white with fine lavender stripes.

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 Hosta 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.  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. (See Sun Tolerant Hostas)

Fertilizer

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, others choose animal manure.  Another organic fertilizer with 8% nitrogen is soybean meal.  Our favorite fertilizer is water, water, and more water.

Mulch

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, spruce needles, or cocoa mulch, as they 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 increase the slug problems, so it is best to avoid this mulch. Regardless of the type of mulch you choose to use, do not mulch deeper than 2-3 inches.  In many cases over-mulching has led to vole problems by providing a nice warm medium that is easy to tunnel through.

Water

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 1½ inches per week, or ½ 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.

Tree Root Competition

Hostas have trouble competing with shallow rooted trees and shrubs.  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 root growth.  This container planting also has been recommended in cases where voles are an extreme Hosta "predator".  If you use a container you need to keep the holes in the bottom open to ensure good drainage. (See Tree Root Invasion)

Pests

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.  (See Dealing with Slugs)

The next most significant problem that is occurring on occasion is crown rot.  In the South this rot will become a problem in the summer when the extreme heat, humidity, and moisture cause the crown to rot and the leaves to pull off the plant.  In the North, this problem is visible in the early spring because water has sat on the Hosta crown during the winter and the plant fails to start growing. 

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, eventually causing the entire leaf to die.  Sanitation is the best control.

Hosta Virus X is a new pest that causes the leaves to become mottled and twisted.  This deformity has no cure.  If your plants contact this virus, also called HVX, the plant must be destroyed.  Fortunately, it does not easily spread to other hostas in your garden. 

The last pest of significance are voles.  These are like mice that have short tails and burrow in the soil like moles.  While moles are not a problem because they eat grubs, voles prefer to eat fleshy roots such as those found on Hostas.  Voles can kill an entire hosta garden over winter.  Control is usually with baits and traps used to catch mice.  Predators include cats, dogs, and birds.

Planting Season

Hostas can be planted 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. 

Uses For Hostas

• Border/Edger planting – Hostas for the border are generally 12 inches or less in height but have increased horizontal growth.  By overhanging a lawn edge they are able to control weeds as they leave no room or light for them.
• Background planting – Large green hostas will show off more colorful varieties of plants.  Hostas that emerge with tremendous color but fade to all green and are great background plants.
• Specimen planting – unusual hostas that are your favorite plants are allowed to grow into very large clumps.
• Ground cover planting – Hostas that are fast growers and form a thick mat of roots and plants will cover the ground and prevent weed growth.
• They can be a natural brightener for shady or dark gardens if you use yellow and mostly white hostas.

Hostas are very beautiful plants. Your appreciation of the Hosta will be cultivated to a higher level by taking a closer look at various aspects of the Hosta.

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