Landscaping under trees | The Real Dirt – Chico Enterprise-Record
The residents of the northern state appreciate tall trees for their beauty and the shade they offer. Older trees have other environmental benefits as well. They promote biological diversity, offset CO2 emissions and reduce energy costs for homeowners.
Shade trees also create a challenging environment for many landscaping plants that the home gardener would like to grow under their branches. Light and moisture, basic growth requirements for all plants, are often limited under trees. The shade that cools the courtyards in summer also restricts plant growth. The soil under old trees is often dry and clogged with water-absorbing roots. In order for underplants to thrive, these obstacles must be overcome.
‘The Real Dirt’ is a columned column by various local master gardeners who are part of Butte County’s UC master gardeners.
When trees are deciduous, their shade is seasonal, and the success of what is planted under them may depend on how early the trees leaf and how dense their canopy is. To open the canopy of a deciduous tree to cast a lighter shade, prune it late in winter. In this way, not only is the tree resting, but its branch structure is fully visible and can be thinned out while maintaining the overall shape of the tree. Remove the lower limbs to a height of at least two meters above the ground to allow sunlight to penetrate the base of dense evergreen plants.
The roots of a tree tend to aggressively snatch every drop of water from the soil, leaving little or no water for underplants growing underneath. One solution to this problem is to water appropriately to meet the needs of the tree and the underplant. Another approach is to grow the desired underplants in pots (with saucers) or in raised beds so that the plants are not in direct competition with trees for water. If you choose to use raised beds, it is a good idea to leave a few inches of space between the bottom of the bed and the floor. If the bed is in direct contact with the ground, tree roots can enter the bed and defeat the purpose of the bed. If a raised bed comes in contact with the ground, it can also affect the uptake of the oxygen that the tree roots need to survive. To save water, it is recommended to install an automated irrigation system with drip irrigation or drinking hoses instead of sprinklers.
Shade-loving plants are physiologically adapted to get by with less light than sun-lovers. Whenever you go to a local nursery to buy plants for a shade garden, check their labels.
Plants labeled as “shade tolerant” or “partial shade” prefer 4 to 6 hours of sun per day. All plants need light, so a plant labeled shade or “full shade” does not mean “no sun”. Rather, these plants prefer less than 4 hours of sun and can actually burn if exposed to more sun, especially in the afternoon.
The following is a partial list of plants that do well in shade gardens in our area.
Those with an asterisk are native to California. Locals tend to be less thirsty, better adapt to our climate, and benefit the wildlife.
Four to six hours of sun a day.
Agapanthus (Agapanthus sp.), Azaleas (Rhododendron indicum), Santa Barbara daisies (Erigeron karvinskianus), bush anemone * (Carpenteria californica), chaparral currant * (Ribes malvaceum), yarrow * (Iris Achillea millefolium), Douglas Iris * (Iris doubles) ), Hummingbird sage * (Salvia spathacea), Idaho fescue * (Festuca idahoensis), rosy buckwheat * (Eriogonum grande var.Rubescens), coffee cherry * (Frangula californica), wild strawberry * (Fragaria vesca)
Full of shadow
Less than four hours of sun a day.
Hellebore (Helleborus sp.), Hog queak (Bergenia crassifolia), creeping Oregon grape * (Mahonia repens), evergreen currant * (Ribes viburnifolium), snowberry * (Symphoricarpos albus), spicebush * (Calycanthus occidentalis), western columbine * (Aquilegia. * formidentalis)).
In addition, almost all of the ferns sold at local nurseries do well for shade or partial shade. Check the label to be sure.
Butte County’s UC Master Gardeners are part of the University of California’s collaborative expansion system and serve our community in a variety of ways, including 4H, farm counselors, and nutrition and exercise programs. To learn more about UCCE Butte County Master Gardeners and get help with gardening in our area, visit https://ucanr.edu/sites/bcmg/. If you have any questions or problems in the garden, call the hotline at 538-7201 or send an email to [email protected]