by Keith Hansen, CEA-Horticulture
One thing East Texans have plenty of is shade. If you live on a cleared lot, wait a few years, do nothing and you'll have trees. Shade is a two-edged sword for the homeowner. On the one hand, it provides welcome relief from our long, hot summers, giving our bodies and our pocketbooks a break from the heat. On the other hand, too much shade can make it difficult to grow many of the outstanding, colorful landscape plants that can really liven up a yard.
This is especially true for perennials. The vast majority of plants known for their striking blooms prefer sunny locations and flower poorly, if at all, in shady areas. Of course, azaleas, and a few other shrubs, are exceptions and bloom wonderfully under shady conditions.
One of the most popular group of perennials in the world are hostas. Hostas are grown not for their blooms but for the spectacular leaves that soften and lighten up the darker areas of a yard. Hostas are said to be the number one perennial in the United States, and are only recently catching on in popularity in Texas.
Hostas are low growing plants with large leaves. Depending on the variety, they grow from twelve inches to 40 inches tall and wide. They come in an astonishing array of leaf colors and forms, which is one reason this group of plants is so interesting and popular. Leaf color ranges from deep green, to chartreuse to almost blue. As a matter of fact, you can identify many of the blue varieties by their names like 'Blue Angel', 'Blue Cadet', etc. On the other end of the leaf color spectrum, there are many variegated varieties sporting cream, white or yellow edges, centers, or blends.
By combining different sizes with different heights, you can create a lot of interest in the shaded areas of the yard with just this one type of plant. They make great groundcovers, growing from late March until fall when they begin to disappear until next year, only to come back fuller. The lush leaves add tropical and cooling effect to the garden. Ferns make nice companion plants for hostas.
Although hostas are grown mainly for their spectacular foliage, they do bloom with tall spikes of flowers, ranging from white to purple. Some varieties also have very fragrant flowers.
Over a thousand varieties have been developed, but only a handful will be available from any retail outlet. If you become addicted to these interesting plants and want to build a collection, there are specialty mail order nurseries to fulfill your passion. I suggest starting out with what's locally available first, since many of the newer, hard-to-find varieties can be quite pricey.
Blue-leaves varieties should be in shadier spots for the bluest color development, while variegated and green types can be planted in areas that get partial sun. Too much sun can bleach the colors of the yellow types.
Hostas like a rich, organic, moist soil. They don't tolerate competition from heavy tree root growth. Avoid planting under elms and other trees with mats of shallow roots. Although they will tolerate (live through) drought, dry soils will cause wilting, yellowing and premature loss of leaves. So, make sure hostas receive plenty of water during the growing season. Drip or trickle irrigation would be ideal for watering hostas. And provide mulch under the plants to conserve moisture. Fertilize in spring with a slow-release fertilizer.
Hostas' biggest enemies are slugs and snails. The large, lush leaves are like a giant dinner plate for these pests which can eat holes in the leaves. The mulch you provide for moisture retention also provides good hiding places for slugs and snails. Beginning when the new leaves first poke out of the ground, use a snail and slug bait, a beer trap or other means to stop these pests. Apparently varieties with thicker leaves are more slug resistant, but in early spring the tender, new growth of all leaves are quite palatable (if you are slug).
We evaluated about 40 hosta varieties in a bed located in the Tyler Rose Garden over a period of several years. All were obtained from local growers in the East Texas area. Out of this group, we found a few that have consistently rated high in appearance over the full growing season. The following varieties are some of the ones that performed the best over the 3 or 4 year rating: Green leaf types - 'Lancifolia' and 'Royal Standard'; blue leaf types - 'Blue Cadet' and 'Blue Angel'; variegated leaves - 'Sugar and Cream', 'So Sweet', 'Albo Marginata' and 'Francee'. We know that there are several other hostas which also are well-adapted to our conditions in northeast Texas.
'Francee' is interesting in that it produces attractive dark green leaves with a narrow border of creamy white which hold up well all growing season, but, it does not emerge from the ground until very late April or even early May.
These varieties and a few others can still be seen in Camellia Garden area on the south side of the Tyler Rose Garden. Other types of plants are also being studied in the same area, including Fargufium, ferns, ginger and others.