Hostas are shade plants, right? Not necessarily. Hostas are usually termed 'shade-tolerant' plants, meaning they will grow in shade or partial shade. But shade might not be their ideal growing condition. Some hostas need a period of full sun to look and perform their best.
The caveat here is that they need a "period" in full sun. It is not recommended that any Hosta is in full sun all the time, or the leaves will burn and brown. But many Hostas are more vigorous and display their most vibrant colors if given at least some sun exposure.
A Quick Rule of Thumb for Hosta Sun Exposure
Hostas with yellow leaves or fragrant flowers can stand more sun than Hostas with green, blue or white leaves.
There are, of course, always exceptions and you may know of a Hosta that is basking and thriving in full sun, but that is not a rule.
Hostas for Full Sun: Yellow and Fragrant Hostas.
In general, yellow hostas need to be planted in a partially sunny location to keep their yellow color vibrant. Without at least a couple of hours of full sun, the yellow color will fade to green, or worse, look like a green leaf that is yellowing.
Similarly, fragrant hostas, those in the species Hosta plantaginea, need exposure to the sun to develop their flowers. Hosta plantaginea is one of the most heat tolerant Hosta species.
Keep in mind, the heat experienced in a full sun location can vary from area to area and even during different times of the day. Full sun in the morning hours will not be as intense as the full sun at noon. While yellow and fragrant hostas need some sun exposure, they do not like to bake or fry in the sun. So if your site is extremely hot or dry, you will need to keep any hostas left sitting in full sun well watered.
Hostas for Partial Shade: Green, Blue, and White
No hosta is going to thrive in deep shade. They all need some sunlight to photosynthesize. The shade tolerant varieties seem to do best in an exposure of morning sun and afternoon shade Too much sun exposure will result in burned leaves, starting from the edges inward. They will look brown, dry, and papery.
Blue hostas require the most protection from the sun. This is because the blue color is a waxy coating on the leaves. The leaves themselves are a shade of green. The waxy coating gives them a blue tint. In full, hot sun, this waxy coating melts and exposes the green leaf underneath, changing the color of your plant from blue to green. It could also expose the leaves to burning. Spraying the leaves with a pesticide or fertilizer can also cause the waxy coating to melt.
Special Consideration: White Hostas
Unfortunately, only trial and error can tell you which Hostas with white variegation can tolerate full sun without burning. However, the thicker the leaves, the more tolerant they will be of the sun. White variegated Hostas with thin leaves, like 'White Christmas,' should be confined to partial shade to maintain their best appearance.
Another problem with white variegated hostas is that the leaves are white because they have minimal amounts of chlorophyll. In full sun, the chlorophyll levels can increase and cause the leaves to pick up a green cast and look less variegated. So only morning sun is recommended for white variegated hostas and the thinner the leaves, the less sun.
Let Your Hosta Tell You When It’s Had Too Much Sun
You can follow the rules and choose the recommended plants and still not have success. The only real gauge for how sun tolerant a plant is, is how it is performing. Two clear signs tell you your hosta is getting too much sun:
- Browning on the tips or outside edges of leaves
- Dull color or faded spots on leaves
If your Hosta plants aren’t doing as well as you would like, don’t be afraid to move them. Hostas are strong plants and can withstand digging and replanting.
Hostas Demonstrating Full Sun Tolerance Potential
(Suggestions are taken from the American Hosta Society and Home Gardeners’ Recommendations)
- Yellow Hosta: August Moon, Gold Regal, Golden Sculpture Rising Sun, Squash Casserole, Sum, and Substance, Sun Power
- Yellow Variegated Hosta: Gold Standard, Inniswood, Regal Splendor, Sundance
- Fragrant Hosta: Hosta plantaginea, Aphrodite, Fragrant Bouquet, Fried Green Tomatoes', Guacamole, Honeybells, Invincible, Royal Standard, Summer Fragrance, So Sweet, Sugar & Cream
- White Variegated Hosta: Hosta undulata Albomarginata, Francee, Minuteman, Patriot
- Green Hosta: Invincible, Pearl Lake
More Than Usual Sun Tolerance, But Not Full Sun:
- Blue Hosta: Blue Angel, Elegans, Halcyon, Krossa Regal