Burr Medic

Hello, I’m Burr Medic

Botanical Name

Medicago Hispida Syn M. polymorpha 


I am an annual plant of the legume family. This means I am great at fixing nitrogen in your soil. And I have a really deep tap root, which makes it hard to dig me out of your lawn. All of this makes Burr Medic a much despised weed, despite the good I am doing for your soil. I have yellow coloured flowers and set lots of seeds from each flower. These seeds develop into prickles so make walking on your lawn unpleasant.


As a weed, I am great in taking advantage of the poor condition of your soil. I like to grow in soils that are dry and alkaline. And I really love soils that are deficient in nutrients including nitrogen, calcium and phosphorus.


My deep roots may annoy you, but I’m actually working on breaking up the compaction in your soil.


I am best controlled by listening to what I’m telling you about your soil condition! I love growing in soils that are low in nitrogen, calcium and phosphorous, which can be helped by adding organic matter. Otherwise try hand weeding. Just make sure you do this after it has rained, otherwise my deep root will be difficult to dig out. Another method is to use a sharp knife and cut my leaves from my root. This allows the roots to keep working on your impacted soil. Add the leaves, minus seeds to your compost heap.

I can also be controlled by using a biodynamic pepper ( see Biodynamic Peppers) However, weed peppers work best when combined with a weed tea. Weed teas take the nutrients I have accumulated in my leaves and feed them back to the soil.

If you must spray, use an organic weed killer comprised of vinegar, salt and soap. Other ways of controlling me include using organic herbicides like Slasher. I can also be boiled alive by pouring boiling water on my leaves. All these actions should be taken before I flower and set seed!