Moisture Tolerant Perennials

by Cheryl Harrison, Master Gardener

So far, spring 2019 has been one of almost continuous rainfall in southern Ontario. The following plants do not demand boggy soil and are hardy in the regular garden. However, they are all moisture tolerant and are a good choice for poolside or boggy plantings.

Lady’s Mantle (Alchemilla mollis) – I love this plant! It looks especially pretty when planted with hostas and bleeding heart…almost a woodland garden without the trees! Lady’s mantle can take sun, sun/part shade and light shade. They can handle dry or very moist soil. They produce frothy, green flowers that look good in fresh, or dried bouquets. Lady’s mantle is one of those plants that acts as a ground cover with its “mantle” of leaves that grow 30-45 cm. (12-15 in.) high. After a rain, the water droplets will bead and sparkle on the fuzzy leaf surfaces.

Bleeding Heart (Lamprocapnos spectabilis formerly Dicentra spectabilis) – Bleeding heart is one of those old-fashioned flowers that was probably in your grandmother’s garden. It grows to about 30-120 cm. (12-47 in.) high. It will keep flowering from spring and into the summer in moist soil. However, it may go dormant, and disappear, if the soil stays dry but will then re-grow again the following spring. Flowers are an unusual shape and may be pink and white or just plain white.

Lady’s mantle foreground, Bleeding heart background. From the author’s garden.

Joe Pye Weed (Eutrochium purpureum formerly Eupatorium purpureum) – According to one folklore source, this native plant gets it’s name from a colonial-era, indigenous healer named Joe Pye who used the weed to cure fever. This plant grows tall, 100-200 cm (39-78 in) high. With its whorled, lance-shaped leaves and purple flowers, it can be quite an exclamation point in a moist garden.

Joy Pye weed with visitor.

Creeping Jenny (Lysimachia nummularia) – Creeping jenny is one of those plants that you may grow to hate if it gets loose in an area that provides its ideal growing conditions. I like this plant because it is a great ground cover in the moist garden or as a “spiller” in a patio pot of mixed plants. Its brightly coloured chartreuse leaves will draw your attention to a sun/part shade area of the garden. Creeping jenny spreads by rhizomes and grows very low to the ground at just 5-10 cm. (2-4 In.).

Creeping jenny in the author’s garden.

Queen-of-the-Prairie (Filipendula rubra) – I only recently discovered this plant when a friend gave me a seedling from her garden. I have it planted along side our pond where it should do well in the moist to wet soil. This plant can be quite spectacular as it may grow to be as much as 245 cm. (8 ft.) high. I am expecting it to have a pale pink, fragrant flower. I can hardly wait!