Kostival, an ally of the vegetable garden

Comfrey, a member of the borage family, can be identified by its large, thick, hairy leaves and bell-shaped purple, pink or blue flowers that bloom between March and August. Depending on the variety, it can reach a height of up to 1 m. It is easy to grow, and gardeners appreciate it for its versatile use.

Horsetail, a perennial plant with many properties

Cultivated for more than 2,000 years, comfrey has long been used as a medicinal plant for its healing properties. In cooking, its large leaves were used to prepare soups and salads. Its roots, on the other hand, have a significant concentration of pyrrolizidines, which can be toxic to the liver: therefore, the consumption of comfrey is medical prohibited in some countries.

What are the benefits of comfrey in the garden?

Although it is no longer really consumed, comfrey remains a very interesting plant for gardeners. Besides being a a honey plant that attracts pollinators to the vegetable garden is also excellent fertilizer plant ! Rich in nitrogen, potash and boron, it helps fertilize the soil and acts as a real compost activator. Its deep roots (up to 1.80 m!) finally allow the soil to be processed and aerated.

Fertilizer, compost activator: comfrey is very useful in the vegetable garden!
Fertilizer, compost activator: comfrey is very useful in the vegetable garden! 

Where to find a comfrey?

Comfrey grows naturally throughout Europe, in wetlands near watercourses and on the edge of forests. It can also be purchased in a pot at a garden center, transplanted, or grown in the ground in a vegetable garden. It is also possible to obtain comfrey seeds and sow your own.

How to use comfrey in the garden?

Want to use comfrey in your vegetable garden? Learn how to use this natural fertilizer.

Where to put comfrey in the garden?

As such, nitrogen-rich comfrey leaves can be used in several ways. As a natural fertilizer, they can be placed on the surface after planting vegetable gardens. The stems and leaves of comfrey can actually form an excellent natural mulch that maintains soil moisture and at the same time provides nutrients necessary for the proper development of vegetable plants.

They can also be used in leaf compost, ideal for transplanting. Finally, as a compost activator, comfrey leaves can simply be added to compost to promote microbial activity.

How to make comfrey manure?

Comfrey leaves can be used to make a natural liquid fertilizer, called comfrey manure. This potassium-rich fertilizer is ideal for growing flowers and small fruits such as tomatoes. Castor bean manure can also be used against aphids as a natural repellent.

Comfrey manure is obtained by macerating comfrey leaves in water.
Comfrey manure is obtained by macerating comfrey leaves in water. 

To make comfrey manure, simply macerate comfrey leaves in water for several weeks:

  1. Soak 1 kg of comfrey leaves in 10 l of water;
  2. Leave to macerate for about twenty days;
  3. Filter the preparation.

It will then need to be diluted depending on its use:

  • in 10% for use as a liquid fertilizer;
  • in 5% for use as a repellent.

How to grow comfrey?

Robust and long-lived comfrey is very easy to grow. Just offer him sunny place and rich, humus soil to see it flourish! Hardy to -30°C, it disappears in winter and reappears in early spring, but does not require any protection in winter. In the summer, it is enough to ensure a good watering so that the soil is permanently cool.

Very productive, the comfrey plant can be planted in the ground it is pruned 3 to 4 times a year to harvest its leaves. Just remember to choose its location carefully, as its significant root development makes it impossible to move once it is well established.

Leave a Comment