[Back to Ugh Slugs] [Companion Plant]
COMFREY (Symphytum officinale)
Comfrey while useful as a slug trap has many other qualities you may find of value. It is a very hardy perennial. It will grow in moist areas and has the ability to clean and extract nutrients from stagnant or foul water. It sends down long tap roots that can go as deep as 10 feet enabling it to accumulate minerals in its' leaves. These minerals include potassium, calcium, magnesium, iron and phosphorus along with vitamins A, C, and B-12. The leaves contain tons of protein as previously mentioned. When comfrey leaves are composted and returned to enrich the soil all these elements are made available to your plants.
Medicinal qualities: Comfrey has many healing properties to it. Briefly the roots and leaves contain allantoin. Allantoin is a protein with hormonal like qualities to it that stimulate cell proliferation. It is the allantoin that gives comfrey its' reputation for healing wounds, broken bones, burns, sprains, sore joints, dry skin and for reducing the swelling associated with fractures. Fresh, clean comfrey leaves can be used in a poultice to treat these injuries. Comfrey salves are readily available from health food stores. It is not recommended to take comfrey internally as liver damage has been known to occur from extended ingestion.
Topical use is safe as the alkaloids will not penetrate the skin.
Comfrey fertilizer: With its' high levels of potash comfrey tea can be used as an excellent fertilizer for tomato, pepper, cucumber and potato plants. The smell while it is "cooking" is strong. Pick a good sized handful of leaves. Place them in a container with enough water to cover the leaves. Cover and let this cook for 4 weeks in cool weather or 2 weeks in hot weather. Then squeeze the leaves to extract as much juice as possible Strain and use at a rate of 1/3 cup 0f comfrey juice to one gallon of water Use as a foliar feed and soil drench around the plants. Put the solid wastes into the compost pile.
Dried or fresh comfrey leaves have the following percentages of NPK:
Nitrogen: 0.75% Phosphorous: 0.25% Potash: 0.2%
- Light: Full sun with some types accepting partial shade.
- Soil: Preferably nitrogen rich with a fairly neutral pH.
- Planting: Set plants 2 feet apart in an area where you can spare the space for them. Once you have planted comfrey it is there to stay.
- Feeding: For plants that are harvested often do keep them well fed.
- Disease: Comfrey Rust (Melampsorella symphyti) is the biggest problem with comfrey. If you see rust starting immediately remove any infested leaves and destroy. Give the plants a good dose of potassium like some wood ashes. Follow with a good organic fertilizer. Allow ample space for air movement among the plants.
There are some different varieties of comfrey available:
Common comfrey (Symphytum officinale)
The most widely used comfrey with clusters of bell-shaped flowers in white, purple, mauve or rose. This is the most invasive variety of comfrey.
Russian comfrey (S.x uplandicum)
Russian comfreys have the highest levels of protein and allantoin.
Bocking No. 4: Grown generally as a fodder for poultry.
Bocking No. 14: This type has the most allantoin and is said to be the least invasive. We have been told that Bocking No. 14 will pretty much stay where you put it. This would make it the best choice for the home gardener. It does show a good resistance to rust which is often a problem with comfreys and it can tolerate a low level of the disease without harming the plants growth.
Creeping comfrey (S. grandiflorum): A low maintenance groundcover with light yellow flowers and crinkly leaves. Will tolerate shade and chokes out the weeds. May be a good choice for the north side of a wall or house.
Goldsmith comfrey (S. grandiflorum "Goldsmith"): Another less invasive type with light yellow flowers and variegated leaves. Grows to 12 inches in height.
Red comfrey (S. officinale "Rubrum"): Red flowers, wow! Will also grow in shade and has a compact growth habit.
These are available as live plants from Richters Herbs.