The hosta, native to China, Japan and Korea, is a long-lived perennial favored for its lovely foliage and willingness to grow in shade. The large hostas are particularly magnificent, and may take as long as 8 years to reach their mature size, which can be up to 8 feet wide. Hostas come in leaf colors of blue, green, gold and yellow; many are variegated. The best strategy for growing a giant hosta is to first be sure the variety you choose will be large at maturity and then to provide the best possible culture. Some favorite large hostas are Sum and Substance, Blue Umbrellas, Regal Splendor and Big Daddy.
Plant in a shaded spot. Hostas do best with morning sun and afternoon shade. As a general rule, the blue-leaf hostas require the most shade, while those with gold, yellow and white leaves take more sun.
Provide a rich, well-drained soil; working in organic material such as compost or leaf mold will encourage vigorous growth.
Dig a planting hole at least 12 inches deep, with a width one and a half times that of the plant's expected mature size. A large, wide hole is important because the hosta's roots will spread horizontally.
If planting a hosta near other plants, keep its mature size in mind so that it doesn't quickly outgrow its spot.
Place container plants in the soil at the same level they were in the pot. Bare-root plants should be planted with the roots spread over a mound of soil in the planting hole. Water well after planting and apply mulch to help conserve soil moisture.
Feed with a slow-release fertilizer in the spring just as the plant is starting to grow.
Be sure the hosta gets an inch of water each week, either from precipitation or watering. Drooping leaves or burned leaf tips can be a sign that the plant isn't getting enough water. Hostas planted under trees may need extra water.
Propagate your hosta by dividing existing plants, if desired. The American Hosta Society recommends that division be performed early in the spring. Keep new divisions well watered until they are established.
Watch for signs of slugs, which can damage the leaves, particularly of the thin-leaved varieties. There are a number of ways to control slugs; setting out a shallow dish of beer at the same level as the soil is one nontoxic method.
Control for deer if they are a problem in your area. If you do not have a fenced-in garden, spray the leaves with a repellant after each rain to deter deer from eating the hostas.