- 14 Jan 2010
Looks like a thriving infestation of dandelions (Taraxacum officinale).
First thing, mow right away before they set seed, that will help reduce the risk of seeding a whole new crop, though the seeds do float for long distances so some will inevitably drift in.
There are two ways to get rid of them. You can apply a selective herbicide, which kills broad-leaf weeds but leaves grass intact. Check with your local garden centre. Some granular lawn dressings contain these herbicides as well as fertilisers, or they are available as liquids for spraying or watering on. Take great care spraying herbicides, if the drops drift in the wind they can damage your valued plants, or worse, the neighbour's. In my experience dandelions are among the easier weeds to kill with selective herbicides. There is more advice on the RHS advice pages:
if the link works, or go to Gardening/Advice/Problems/Lawns:weed control
Or, if you have time and patience (and this isnt a very large plot), you can use an old kitchen knife to cut them off well below ground level. There is a flat rosette of leaves attached to a deep, fleshy taproot. Stick the knife in at an angle to cut the root as far below ground as possible and hoick the plant out. Rather a satisfying proceedure, I find. You do need to cut deep, because they will regrow from the remaining bit of root from quite deep down.