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.
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.
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 in your garden should be amended with compost to a depth of 12-18 inches. Prepare the soil according to the Soil Preparation Guide. Place the Hosta in the hole so that the plant crown is level with the ground. Place some good soil around the roots and water thoroughly. Space the plants 2 to 4 feet apart, allowing room for them to grow. 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 necessary shade that hostas love. 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.
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 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.
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.
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 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.
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.
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 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.
Pests and Diseases
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. Planting Season
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.
A newer concern among hosta growers is the appearance of a virus, known as Hosta Virus X (HVX) in commercially grown plants and contaminating home gardens. The virus is spread by infected sap (plant fluids), either by contaminated water (in commercial propogation) or by contaminated garden tools. 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 with a bleach solution between contact with individual plants.
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