Though "hostas" are often thought of as a single entity, differences in growth rates between varieties require specialized techniques. At the same time, other perennials require growing methods specific to their needs. Time of year also influences how a plant is handled. Generally, plants potted beyond mid-summer must be handled differently than those potted earlier. Our information reflects some of the knowledge that we've gained in these areas over fifteen years of growing our liners and 2 1/4" plants into saleable quart or gallon-sized plants in outdoor beds.

The final pot size depends upon the mature size of the plant. For example, a huge plant like 'Sum and Substance' would best be grown in a two-gallon container while quart containers work better for dwarf hostas such as "Tiny Tears.' The soil mix we've used has been a fairly standard peat-perlite blend-good aeration and moisture retention.

Super-phosphate and/or slow-release fertilizers can be added to the mix, but we prefer liquid feeding to give us more control of soil nutrient levels. The amount and type of nitrogen and frequency of feeding varies by time of year. Generally, fertilizer is injected with every watering from May through August. After September 1 the fertilization is gradually reduced and finally stopped by early October. Soil pH greatly influences the absorption of various fertilizer nutrients. A pH between 6.0 and 6.5 has proven optimal for growing hostas in containers. Hostas grown in alkaline soil (above pH 7.0) often develop iron deficiencies. An iron deficient hosta will turn chlorotic between the veins. Such plants may not look very saleable but may actually have extensive root systems and good foliar development. Acid injection during watering is the easiest way to combat such a problem.
 

Lighting conditions are, of course, a crucial part of growing any type of plant. Containerized hostas grown in outdoor beds in northern Illinois benefit from the addition of 60% shadecloth over the growing area. Shadecloth should be added no later than the first of June and removed around the first of October. Other perennials also can benefit from supplemental shade, especially in July and August. 30% shadecloth can be helpful in growing Pulmonarias.