What to Plant Beneath Evergreens?

What to Plant Beneath Evergreen Trees?

Q: Lisa Johnson – What is the best grass to seed in shaded areas under fir trees?

A: Hi Lisa, I get asked all the time about what will grow under evergreens. Dry shade is the toughest place to grow in! My best bit of advice is that nothing will survive directly under the canopy. It’s just too dry! A better plan is to use a cedar or stone mulch directly beneath the boughs. However, if the area in question gets at least ½ a day of sun (6 hours) and gets wet when it rains, here are some alternatives:

Creeping Red Fescue Grass Thrives in Shade

Grass for Shady Areas:
To establish a lawn just beyond the ‘drip line’ in an area around the fir trees, seed the shade-tolerant grass-Creeping Red Fescue. Red fescue (Festuca rubra) is an Edmonton hardy grass ideal for use around trees as the grass has a very high tolerance for shade and thrives with low amounts of water, fertilizer and mowing. The grass has very fine leaves and a dark-green color and has a slow growth rate. Red fescue has low tolerance for heat except when planted in areas of shade. The grass establishes slowly and has a moderate level of resistance to wear.

Alternatively, you may consider growing perennials groundcover plants beneath evergreen trees. This will be a challenge, because spruce and pine have low overhanging branches can create an extremely shady and dry place to grow. Remember surviving is not thriving! Ideally, you would mulch directly below the branches, and plant the perennials beyond the drip line (past the edge of the tips of the branches).

Perennial Groundcover Alternatives to Grass for Dry Shade:

Shade loving Bishop's Cap Perennial Groundcover

Elephant Ears(Bergenia), Bugle Weed, Creeping Jenny, Gout Weed, Lily of the Valley, Bunchberry (Cornus canadensis), False Nettle(Lamiastrum), Lamium, Bishop’s Cap, Euphorbia, Perennial Geranium, Stonecrop, and Solomon’s Seal.

Growing Tips for Dry Shade:
Plants beneath the branches must compete with shallow and wide spreading tree roots for water and nutrients. Contrary to popular belief, tree roots generally don’t penetrate great soil depths, but are found within the top 30 cm (6”) of the soil.

For anything to survive dry shade, you have to water and fertilize. Water deeply and frequently and use foliar fertilizer like 20-20-20 at a rate of 1 tbsp/ 4L instead of soil applied fertilizer to ensure that the understory plants receive the nutrients.

Falling evergreen needles will slowly increase the acidity of the soil to levels that many plants cannot tolerate. In some cases, a tree may shed so many needles that the lawn or plants below simply become smothered. Don’t fight nature – go with the flow! Needles are an excellent mulch.