Ask the Master Gardener: The keys to successful planting in shaded areas
Gardening in full shade can be a little challenging, but planting perennials can thrive in such conditions.
Dear Master Gardener: We have some large areas under white pines where grass struggles to grow. We are thinking about planting perennials for easier care. The areas are full shade with a few spots of filtered shade. We live in Crosby and would be very appreciative if you would give us some direction.
All of the plants listed below perform well in shade and are deer resistant, with the exception of hostas, which are deer candy.
Variegated Solomon’s Seal has bright green foliage with white edging, maroon-tinged stems, and dangling white bell-shaped flowers. It attracts bees and butterflies, its berries are attractive to birds, and it tolerates heavy shade.
Hostas -- there is a large variety, but as a general rule, blue, green, and variegated will do best in full shade. Avoid hostas with yellow or gold (often they have “sun” as part of their name) or Hosta Plantaginea because those hostas need sunlight for their coloration or flowers. Hostas with blue leaves prefer shade and will hold their color more in shade.
Tiarella (foamflower) has beautiful foliage and airy, pinkish-white flowers that bloom for about six weeks in early summer.
Pulmonaria blooms in spring -- some cultivar flowers come in purple, pink, blue, or a combination of the three. There is a white cultivar called Sissinghurst White. The foliage on many of the cultivars is stunning with silver splotches, silver or white polka dots, or silvery foliage with green splotches.
Ferns thrive in shade or filtered light. Lady in Red has bright green foliage with deep burgundy-red stems. Ghost has upright, silvery-white fronds and pinkish-purple stems. Both get about two feet tall. Cinnamon Fern is vase-shaped, reaches 60 inches in height, and gets its name from its “cinnamon stick” fronds. Ostrich Fern is one of the most well-known and easiest to grow. It attains a height of 60 inches and the cultivar The King attains a height of 72 inches. This plant spreads rapidly. Goldie’s Wood Fern is a large fern with leathery fronds that can be more than one-foot wide – forming a very impressive plant. All these ferns need lots of moisture.
Bleeding hearts thrive in light to full shade, but may flower more if you put them in the areas where you have filtered light.
Virginia bluebells bloom in spring and are native to Minnesota. The flowers start off pink, then turn to a beautiful blue. The blooms last for many weeks, then the plant goes dormant by mid-summer.
Bergenia, another spring blooming plant, has distinctive heart-shaped, leathery, glossy, dark green leaves. Small dark pink flowers appear within or above the foliage on stout stalks reaching about sixteen inches tall. This plant will flower better if you have it in the areas where you get some filtered light. Do not cut this perennial down in the fall.
Wintergreen is a creeping, woody evergreen groundcover native to Minnesota woodlands.
Snow-on-the-mountain (also known as bishop’s weed) – if you need a little plant to cover a large area, this is a vigorous groundcover that is great for filling shady spots. It has variegated green-and-white leaves with clusters of white flowers that bloom in summer. It tolerates poor soil and shade. Use it with caution - it will spread aggressively!
Canadian wild ginger is a Minnesota native plant that has green, heart-shaped leaves and if you look carefully, you will find a small flower near the ground in spring. Wild ginger tends to grow in colonies and spread by rhizomes. It makes a great ground cover for a shady area.
Lily-of-the-valley is slow to spread but long lived once established, forming dense colonies. It has green, oval-shaped leaves with fragrant, white, bell-shaped flowers that bloom in May or June. It gets 4-10 inches high.
October Gardening Tips
Time to clean out and put away your hummingbird feeders. The ruby-throated hummingbirds usually leave our area for warmer climates by the end of September.
Pick tomatoes and peppers and bring them inside as soon as there is a threat of frost. Tomatoes will ripen further indoors, peppers will not.
Light frost won’t harm all vegetable plants -- cabbage, kale, broccoli, brussels sprouts, and kohlrabi develop milder flavor when exposed to frost.
It’s a myth that apples need frost to develop good flavor. Pick them as soon as they are ripe.
Leave a couple inches of stem attached when you pick pumpkins. They must be harvested or protected if frost is in the forecast because they have no frost tolerance.
Plant spring blooming bulbs by mid-October. Children often enjoy planting bulbs, so it can be a fun gardening project to do together. If you have had bad luck with chipmunks and squirrels digging up and eating your bulbs, you can place chicken wire or hardware cloth over the area. Just remember to take it off in spring.
Protect hybrid tea and other non-hardy roses by mid-month. Some years you can wait longer, but it’s a risk. Mound soil over the crowns or tie canes together, then tip them into trenches. Just rake leaves over the base of hardy roses. No Styrofoam cones -- they collect moisture inside, which can lead to disease. Excess heat building up in the spring can cause the rose to break dormancy too soon.
Wait to cut back perennials until their foliage is damaged by frost. They will continue to photosynthesize as long as they are green and healthy.
Continue to mow the lawn as needed to a height of three inches. Rake the lawn so it doesn’t mat down and encourage snow mold development.
Keep watering trees, shrubs, and especially evergreens until the soil freezes to minimize desiccation from dry winter winds.
Cover strawberry plants with clean straw to protect their crowns.
Store your favorite geraniums in pots over the winter. Put them by a basement window or bright window upstairs. Water often enough to keep them from shriveling.
Clean and oil garden tools before storing them for the winter.
You may get your garden questions answered by calling the new Master Gardener Help Line at 218-824-1068 and leaving a message. A Master Gardener will return your call. Or, emailing me at email@example.com and I will answer you in the column if space allows.
University of Minnesota Extension Master Gardeners are trained and certified volunteers for the University of Minnesota Extension. Information given in this column is based on university research.