If you are planning to grow wildflowers in grassy areas, then Autumn is the ideal time to plant wildflower plugs. It gives the plants enough time to establish their root system ahead of spring. It means that when spring arrives and the soil warms up, the established plants are better able to compete against the fast growing grass.
The best thing to do, is to mow the grass as short as you possibly can, remove all the cuttings (pop them in the compost) and then plant the plugs as quickly as you can (i.e on the same day). Use a trowel or dibber to make holes so that you can push the wildflower plugs into the soil and firm them in well. This shouldn’t be too difficult as the soil is a little more moist at this time of year. Be sure to soak the plug plants, as per the growing guide, so that their root balls are moist when you plant them. Should the soil become dry during the first two weeks or so of planting, you will need to water them, but with the odd rain shower, they should be just fine.
Bearing in mind that each plug contains several different seeds/seedlings of different wildflower species, you can make your own decision as to how densely you wish to plant. We’d suggest that anything from five plugs to twenty plugs per square metre is sensible and not too laborious a task! Although, you may want to plant even more densely than this for a more abundant display.