The challenge tugs at your garden gloves, causing you to try, try again for planting success. Its name is dry shade and it can leave you with bare ground where you want greenery. Drought-tolerant Salvias and companion plants, including ornamental grasses, can play a role in conquering dry shade, but first you need to understand how to work with it and improve chances for plant survival.
Understanding Dry Shade
Dry shade mostly occurs under and near trees. Their shady canopies prevent full rainfall from reaching the ground; their thirsty roots soak up available moisture leaving little for other plants. Dry shade also occurs next to shrubs along shady fences or at the foundation of buildings under deep roof overhangs.
Depending on the thickness of a tree's leafy canopy or the location of a fence or foundation bed, a dry shade area may be located in partial or full shade.
Partial shade, also called "dappled sunlight" or "broken shade" is the best kind for many plants, including Salvias. In this situation, plants receive a sufficient amount of direct or lightly filtered sunlight.
Full shade is also known as "deep" shade and occurs under trees, such as Conifers, with dense canopies or on the north side of structures. The companion plants listed here do well both in partial and deep shade.
Improving Moisture Retention
To aid plants in surviving dry shade conditions, it helps to improve soil with organic matter, such as compost or decaying leaves. Aside from providing nutrients, organic matter breaks up soil and improves aeration, which is necessary for oxygen-hungry roots.
If you turning large quantities of soil near or under trees and shrubs, you likely will destroy many of hair-like, feeder roots. Maples are particularly well known for their abundance of shallow roots. However, the roots of most trees grow within the first 6 to 24 inches of soil.
So, instead of digging in organic matter, it is best to spread a thin layer -- perhaps 3 inches or less -- on the soil surface. There it can act as mulch, decay and be dragged underground by earthworms. Avoid thick layering or building raised beds under trees and shrubs so you don't cut off oxygen to roots.
Planting in Pockets
Planting infrequently under and near trees and shrubs offers the least disturbance of roots. That means that it's better to plant perennials than annuals. Also, it's best to pocket plant small sets -- ones in 4-inch containers or smaller.
Using a hand trowel, make each planting hole, or pocket, about a third larger than the root ball. Replace half of the soil with compost and mix it well so it won't burn the plant's roots. Place the root ball in the hole and fill in around it with this soil mix, making sure that the top of the root ball is even with the surface of the ground.
Some plants are made for shade, particularly woodland species such as Heuchera and Stachys. Others do well in shade, but particularly thrive in full sun. Foliage and bloom of sun loving plants may not be as lush as you would like in dry shade. However, you can create a fuller look by planting species with varying sizes and shapes of foliage. For example, by combining Heucheras with Big Pitcher Sage or West Texas Grass Sage, you mix together a basal mat of decorative, scalloped leaves with thin, long, blade-like leaves.
Also, patience is important. Although some perennials grow as quickly as annuals, others are slow, but fill out over time.
Choosing Salvias and Companion Plants
Please note that the following list of extremely drought-resistant plants is grouped according to the chilliest winter weather they can survive. Plants in the colder zones certainly are good choices for the warmer climes of Zone 7 and beyond.
Please keep in mind that plants adaptable to partial shade show laxness if they receive too much shade. This may be a signal to move them to a somewhat sunnier location.
This list is limited to 20 selections. You'll find additional suggestions and cultivation information at our previous blog post 15 Select Salvias for Dry, Partial-Shade Gardening.
Big Pitcher Sage (Salvia pitcheri grandiflora) Zones 4 to 9
Canyon Belle Dwarf Coral Bells (Heuchera 'Canyon Bells') Zones 4 to 9
Canyon Chimes Dwarf Coral Bells (Heuchera 'Canyon Chimes) Zones 4 to 9
Canyon Duet Coral Bells (Heuchera 'Canyon Duet') Zones 4 to 9
Canyon Melody Dwarf Coral Bells (Heuchera 'Canyon Melody') Zones 4 to 9
Wild Sage (Salvia verbenacea) Zones 5 to 9
West Texas Grass Sage (Salvia reptans) Zones 5 to 9
Black Oriental Fountain Grass (Pennisetum alopecuroides 'Moudry') Zones 5 to 9
Karley Rose Oriental Fountain Grass (Pennisetum orientale 'Karley Rose') Zones 5 to 9
Golden Elk Hybrid Jame Sage (Salvia x jamensis 'Golden Elk' ) Zones 6 to 9
Wand Sage (Salvia cadmica) Zones 7 to 10
Elk Pomegranate Autumn Sage (Salvia greggii 'Elk Pomegranate') Zones 7 to 9
Plum Wine Autumn Sage (Salvia greggii 'Plum Wine') Zones 7 to 9
Stormy Pink Autumn Sage (Salvia greggii 'Stormy Pink') Zones 7 to 9
Elk Velvet Mountain Sage (Salvia microphylla ' Elk Velvet') Zones 7 to 9
18th of March Mountain Sage (Salvia microphylla 'Dieciocho de Marzo') Zones 7 to 9
Royal Purple Autumn Sage (Salvia muelleri) Zones 7 to 9
Tamaulipas Mystery Sage (Salvia species from Tamaulipas) Zones 7 to 10
Cherry Queen Hybrid Sage (Salvia x Cherry Queen) Zones 7 to 9
Evergreen Cranesbill (Geranium x cantabrigense 'Biokovo') Zones 7 to 10
Hidalgo or 7-Up Plant (Stachys albotomentosa) Zones 7 to 9
Red Betony (Stachys coccinea) Zones 7 to 9
Thirsting for More Information?
If you have questions that need answering about shade planting or concerning any of our plants, please feel free to contact us. We're glad to share what we know.