Have you been trying to grow perennials under dense spruces or tall, mature maples, but to no success? One after the other, the hostas and astilbes you have planted wither and die? Forget about the shade plants generally proposed on the horticultural market and try indestructible perennials that can withstand even the most extreme conditions!
The shade cast by mature spruces and maples is generally very dense and totally inhospitable. Few plants can grow in such conditions as, in addition to blocking the sunlight, those trees’ thick foliage creates drought conditions by preventing the rain from reaching the ground. But there is worse! The trees’ enormous root systems ferociously compete with the perennials’ rootlets for the absorption of the nutrients and water present in the soil. For example, during a hot July day, a mature silver maple can draw up to 200 litres of water from the soil! Certain species, such as the black walnut tree and chestnut tree, even give off chemical substances called “allelopathic”, which have a toxic effect on the plants that dare try to grow under their canopy. Those are extreme conditions!
If you wish to create a durable plantation under mature trees, you must choose very vigorous plants that are perfectly adapted to drought and low light conditions. The Canadian wild ginger (Asarum canadense), barrenwort (Epimedium), sweet woodruff (Galium odoratum), big-root geranium (Geranium macrorrhizum), mourning widow (Geranium phaeum), ‘Variegatum’ yellow archangel (Lamiastrum galeobdolon ‘Variegatum’) and Solomon’s seals (Polygonatum) are simply indestructible perennials that can withstand the worst conditions. Absence of light, drought, and ferocious competition with tree roots, nothing scares them! They are true warriors!
Canadian wild ginger (Asarum canadense)
Height: 20 cm Width: 30 cm Flowering: brown in May and June Foliage: green, velvety, heart-shaped Light: sun, partial shade, light shade, medium shade, deep shade Soil: rich and cool Hardiness: zone 3
‘Bevan’s Variety’ big-root geranium (Geranium macrorrhizum ‘Bevan’s Variety’)
Height: 40 cm Width: 60 cm Flowering: magenta-pink in June and July Foliage: palmate leaves, cut and dentate, of medium green colour Light: sun, partial shade, light shade, medium shade, deep shade Soil: adapts to various types of well-drained soils Hardiness: zone 3
‘Variegatum’ yellow archangel (Lamiastrum galeobdolon ‘Variegatum’)
Height: 30 cm Width: 1.50 m Flowering: yellow from May through July Foliage: ovate, dentate leaves, green in colour with grey marks Light: sun, partial shade, light shade, medium shade, deep shade Soil: adapts to various cool, well-drained soils Hardiness: zone 3
Scented Solomon’s seal
Height: 80 cm Width: 30 cm Flowering: white and green in May and early June Light: partial shade, light shade, medium shade, deep shade Soil: rich and cool, well-drained Hardiness: zone 4