Evergreen clumps throw up honey-bearing flowers in late spring and early summer, while roots drive deep enough to mine rare trace elements out of the subsoil. Comfrey (Symphytum) is grown for fertiliser, mulch and pollinators alike; plant it where it meets real competition for space and it will feed the garden for years.
| Latin name | Symphitum sp. |
|---|---|
| Common name | Comfrey |
| Family | Boraginaceae |
| Type | Perennial |
| Height | 1 to 4 feet (30 cm to 1.20 m), depending on species |
| Planting density | 6 to 8 plants for 10 square feet (1 m²) |
| Exposure | Preferably semi-shaded |
| Soil | Any |
| Flowering | Late spring, early summer |
| Foliage | Evergreen |
Comfrey is a perennial plant often seen as a wild and generous gift of nature. It’s a boon for gardeners, providing remedies for their garden, and a feast for pollinators with its honey-bearing flowers. Let’s delve into everything there is to know about comfrey and its multitude of benefits.
Comfrey, as a low-maintenance perennial, is a breeze to plant. No soil prep is needed, and you can plant it either in fall or spring.
However, choose your location wisely. Go for a spot that’s sunny to semi-shaded. Moreover, ensure your comfrey gets planted where it finds strong competition for space, so that the plants can self-regulate. Indeed, this perennial can quickly take over a vast space, and it’s no easy task uprooting it.
Smart Tip: After planting your comfrey, apply natural mulch on the soil. It will retain soil moisture, something this perennial truly appreciates.
When planting it for the first time, you might need to keep an eye on watering. Provide moderate but regular water in case of long dry spells.
After roots have dug deep, all you need to do is renew foliage by cutting back the clump after flowering.
→ Tip: spread these nutrient-packed leaves under ornamentals and vegetables as a nutritious mulch.
If summer’s too dry, wait for rains to do your trimming. If your comfrey starts to spread too much, don’t hesitate to control it with a sharp spade to remove extending stems.
Often, the simplest way to multiply a comfrey plant is to divide it. Dig up all or part of the plant in fall, split the clump. Replant the new plants following our planting advice.
Comfrey is a sturdy perennial untouched by diseases. Pests don’t seem to have an impact either, except perhaps flea beetle that bores holes in leaves, especially during dry springs (they hate moisture).
Strength of comfrey lies in its numerous qualities, whether in garden or kitchen. When you use leaves, it’s better to harvest them at dawn if you use them fresh, or mid-afternoon if you plan on drying them.
Comfrey leaves are known for the comfrey manure they produce. The deep roots are able to extract rare trace elements from the soil, making the plant a valuable source of fertilizer.
But don’t forget the flowers! Some species like tuberous comfrey (Symphytum tuberosum) are particularly floriferous and recommended for attracting pollinators.
You can prepare foliage like spinach, either raw or cooked. However, keep consumption limited as it contains alkaloids that can be toxic to liver with too regular ingestion.
Comfrey earns its place through several quite different jobs, from feeding the vegetable patch to feeding the bees. Here is what each use asks of you.
| Use | Part used | What it gives | How to do it |
|---|---|---|---|
| Liquid fertiliser (comfrey manure) | Leaves | Rare trace elements drawn up by the deep roots | Harvest leaves at dawn when you use them fresh |
| Mulch | Leaves cut back after flowering | Nutrients for ornamentals and vegetables | Spread the cut foliage on the soil surface |
| Feeding pollinators | Flowers | Honey-bearing blooms in late spring and early summer | Grow floriferous species such as tuberous comfrey |
| Kitchen use | Foliage | A spinach-like vegetable, raw or cooked | Eat sparingly only, as the alkaloids harm the liver |
Whatever the use, leaves destined for drying are better cut in the mid-afternoon.
Comfreys fall into two camps: the big leafy strains grown as a fertiliser crop, and the low, spreading kinds used as ground cover in shade. The table below sets out the ones commonly offered as plants, root cuttings or seed.
| Variety | Flower colour | Habit | Best use | Position |
|---|---|---|---|---|
| Russian comfrey | Blue to violet | Tall, coarse clump | Heavy leaf yield for mulch; good for bees | Sun to semi-shade |
| ‘Hidcote Blue’ | Pale blue, red in bud | Low, spreading | Weed-suppressing ground cover | Dry shade |
| ‘Hidcote Pink’ | Pink fading to white | Low, spreading | Ground cover at shrub bases | Dry shade |
| ‘Album’ | White | Medium clump | Informal and wildlife borders | Semi-shade |
| ‘Axminster Gold’ | Violet-blue | Tall, gold-margined leaves | Bold foliage plant | Semi-shade |
| ‘Variegatum’ | Blue-violet | Medium clump, cream-edged leaves | Foliage accent in shaded borders | Semi-shade; scorches in hot sun |
| ‘Rubrum’ | Deep crimson-red | Low, compact, slow | Long-flowering front-of-border plant for bees | Semi-shade, moist soil |
| ‘Bocking 14’ | Mauve-purple | Tall, clump-forming | Liquid feed and mulch; sterile, no self-seeding | Sun to semi-shade |
| ‘Goldsmith’ | Pale blue and cream | Low, spreading | Variegated ground cover, edging | Shade to semi-shade |
Comfrey is a perfect plant to adorn a flower bed, a slope, or to ornament base of a deciduous shrub. Even though you can pair it with any perennial in your garden, prefer to set it up with plants that don’t mind competition like lungworts, perennial geraniums or ferns.
