Dave, who works one of the neighbouring plots to ours has been very generous during our fiirst year at Dingle Vale. It was he who, when we were late getting the greenhouse assembled, gave us his surplus tomato plants, enough to fill the greenhouse. Good varieties, very varied, and which have cropped heavily.
From time to time he’s also given us bottles of comfrey liquid fertiliser that he makes himself. Now he’s given us half a dozen comfrey plants so that we can do it for ourselves. Comfrey is a particularly valuable fertiliser, because it is very deep rooted and acts as a dynamic accumulator, mining a host of nutrients from the soil. These are then made available through its fast growing leaves (up to 4-5 pounds per plant per cut) which, because they lack fibre, quickly break down to a thick black liquid. Comfrey is an excellent source of potassium, an essential plant nutrient needed for flower, seed and fruit production. Its leaves contain 2-3 times more potassium than farmyard manure, mined from deep in the subsoil, tapping into reserves that would not normally be available to plants.
To make comfrey fertiliser:
Comfrey leaves should be crammed into a large container with a hole in the bottom with a small container underneath to catch the thick black liquid which will be produced in a few weeks. Weighing the comfrey down with an old brick will help this process and some people add rainwater but this does make the resulting ‘comfrey tea’ smell awful! Once produced, the liquid should be diluted 15:1 with water before using it as a feed for plants such as tomatoes.
- As a compost activator – comfrey is so rich that it not only enriches your heaps but encourages them to heat up.
- The first cut of the year, in spring, should go in to the furrow before the potatoes. The liquid feed will also be good for potatoes as will chopped wilted leaves as a mulch – before the foliage gets too dense to effectively spread it.
- As a mulch and as a liquid feed for tomatoes, runner and dwarf beans.
- Mix with leafmould to make a base for potting compost.
The site adds this on maintenance in the first couple of years:
Comfrey is a pretty tough plant that will grow from small pieces of root so do choose your location with care. It is easier to kill most weeds than comfrey. If you do need to move a comfrey bed the old bed will need to be killed off. Your best bet will be to use a weedkiller like ammonium sulphamate. Comfrey will thrive in full sun or in partial to near full shade – there is usually a disused corner that will make a great site for your comfrey bed.
Block plant around 2 to 3 feet apart and stand back. You will be surprised how quickly they grow. When the flowers appear take a cut. I use a pair of shears and cut about 6 inches from the ground. Comfrey has little hairs on the leaves, which can irritate. Not quite a cactus but near, so wear gloves. Come winter the plants go dormant and a good layer of manure can be applied.
In the second year your comfrey patch starts to really pay off. In the spring it will leap back from its winter sleep. Your first cut will get the spuds off to a good start. After that you should get at least a further 3 cuts – even 4.
To get further plants, push your spade through the middle of a plant and lever up a portion. Take root cuttings (about 2 inches long) and away you go again. Be careful as the bits left over will happily root wherever they fall.