Comfrey is more than just a plant you often find along railway embankments. This 'old-fashioned' plant can be used medicinally and can serve as a nutrient for your vegetable garden. The large hairy leaves contain the three macro-nutrients N (nitrogen), P (phosphorus), and K (potassium), which you also find in the vegetable garden fertilizers you can buy everywhere. Get one comfrey plant, and you can propagate them annually. Use comfrey from the flowering stage onwards for your fruit bushes, fruit trees, and fruit crops. For potatoes, brassicas, leafy greens, and greedy tubers like celeriac and beetroot, you can start using comfrey after transplanting. Root crops and legumes do not benefit from these nutrients.
Tom
I use comfrey in three ways in my vegetable garden. I process the leaves into liquid fertilizer, roughly chop the branches for mulch, and use excess leaves and branches in our compost as a compost accelerator.
Comfrey: nutrient in the vegetable garden - comfrey liquid fertilizer
You can make comfrey liquid fertilizer as follows:
- Wear long pants, a sweater, and gloves. You can get skin irritation from comfrey.
- Fill a bucket with comfrey leaves, don't cram them in, but press them down a little and put a stone on top.
- Fill the bucket with water and put the comfrey leaves just under water (as if you were making vegetable soup).
- When the leaves have almost dissolved (3 to 6 weeks), a brown, syrupy substance remains. The smell is terrible; this is completely normal, even good.
- Strain the comfrey through a sieve again. It works easier if your watering can has a spray nozzle.
- Create a ratio of 10% comfrey fertilizer / 90% water and use it in the vegetable garden.
TIP: if you work with a container that has a tap at the bottom, you can just keep adding leaves, a stone, and water at the top. Comfrey fertilizer has, for example, an NPK of 8-3-20, very strong to use directly in the garden, which is why so much water is added. N8 (nitrogen) ensures good leaf growth for your plants, P3 (phosphorus) helps your plants in their fight against diseases, and K20 (potassium) ensures flowering, nice tubers, and full fruits. In addition, comfrey contains free manganese and calcium, two super important building blocks for plants.
Comfrey: nutrient in the vegetable garden - mulching with comfrey
A second way to use comfrey is to use the leaves as mulch. A mulch layer is a layer of organic material (in this case comfrey leaves) that covers your soil. The goal is to feed the soil organisms in your important top layer of 15-20 cm from above. Mulch also keeps your top layer nicely moist, as it retains moisture in the ground better than bare soil does. As a bonus, you also get fewer weeds, as dormant (weed) seeds in your ground are also shielded from light. Avoid getting the comfrey leaves into the soil; if they decompose there, they require nitrogen to do so, and we prefer to keep that for our plants.
Comfrey can be found in nature along railway embankments, canals, and forest edges. You can also order a comfrey plant on this site. After a year, you can split the root system and plants and replant them. Comfrey grows very easily, creates a very deep root system, and loves a spot in a sunny to half-sunny location. Note! Comfrey throws its seeds on the ground after flowering and has a tendency to spread aggressively. You can avoid this by pruning the flowers when there are signs that they are starting to die OR by ordering the Bocking 14 variant, which does not self-seed.
Comfrey: nutrient in the vegetable garden - comfrey liquid fertilizer as a spray
You can also spray comfrey liquid fertilizer on your leaves. It slows down mildew.
Comfrey: nutrient in the vegetable garden - comfrey activates your compost heap
Comfrey leaves can also be used as a compost activator. Especially when your compost contains a lot of brown material (branches and leaves). Place a double layer of comfrey leaves on your compost heap and sprinkle some garden soil on it. The fast-rotting leaves leave behind quite a bit of nitrogen. That nitrogen will work with the existing bacteria and soil organisms to jumpstart or accelerate the composting process of your brown material. Good luck!
