Wildflowers to sow in August and early Autumn

Why should I sow Wildflowers in August?

In considering what flowers to sow now I was fascinated by the thought of making a distinction between growing wildflowers or growing for wildlife and what to suggest. Maybe because I have misread the brief…

In looking further it appears that many of what we would consider native wildflowers have been introduced but before the 1500s and have naturalised. We also grow flowers in our gardens that are a wildflower elsewhere e.g. californian poppy. Both will be beneficial for wildlife. Native wildflowers act as food for certain types of caterpillars and more recent introductions are plants and flowers that we increasingly grow as a source of food for many insects.

What to sow…

Biennials and perennial wildflowers are often best sown at this time of year 

Biennials: e.g Wild Carrot, Viper’s Bugloss, Woad, Common Foxglove, Teasels and Forget-me-nots.

Perennials: e.g. Garlic mustard - also known as Jack by the Hedge, Birdsfoot Trefoil, Yarrow (Achillea millefolium) and Self Heal. Which will often germinate and establish themselves before the winter weather closes in although there are a few that will only germinate in spring after exposure to cold..

Hardy Annuals: e.g. Field poppies, Welsh poppies and other hardy poppies. Cornflower, 

Many of these can also be sown in spring. If your garden tends to get waterlogged then this would be the better option to prevent seeds rotting in the ground unless you can provide a sheltered space.

Why sow in August?

Some seeds will germinate and grow to a size where they will weather the winter. E.g. Chicory, others will lie in the soil but need one or more periods of cold to ready the seed for germination in the spring. E.g. Yellow rattle, Bluebells, Cow Parsley, Primroses and Cowslips.

Where to sow

Some plants including Viper’s Bugloss are best sown in situ, that is diirect on the soil. Others can be sown in seed trays and either germinated inside or placed in a sheltered position to germinate outside. Once they are large enough to plant out they can then be planted in the garden to overwinter.

Should I sow in seed trays or on the ground?

For many of the autumn sown plants they require cold to germinate. If you use seed trays, which have the advantage of being able to see the required seed as it germinates but keep them at the correct temperature for seed germination - if you have a cool greenhouse or cold frame this can be ideal, if not a sheltered place in the garden where they are protected from too much rain and local cats.

However some plants such as Viper’s Bugloss, Cow Parsley, Teasel, Chicory (Cichorium intubus) and Wild Carrot have a tap root so they are best sown directly on the ground where they are to flower.

Tips

If broadcasting on the ground, mix the seed with sand to help the dispersion of the seed and to avoid the need for thinning seedlings where the seed has clumped. This is especially useful for very small seed.

Remember to label them well so come spring you will know what they are!

A Note on Yellow Rattle

An annual plant that in recent years has been well promoted as a parasitic plant which aids the establishment of annual meadows and wildflower areas due to it’s parasitic nature on grass.  It also needs frost to germinate so sow from August to the end November.

For more information on how to grow Yellow Rattle visit our Yellow Rattle Page

Sowing in Autumn for wildlife.

Many plants that are good for wildlife have been mentioned in the wildflowers section above for example Teasel and Bird’s Foot Trefoil.

Other more traditional cottage garden plants are also useful additions that are good for sowing in Autumn.

Calendulas - the Pot Marigolds, Violas and Pansies, Borage, Cerinthe, Ammis, Scabious, Nigella, Gypsophila and so on. In milder areas then Antirrhinums are also good to sow now but make sure they are protected it we have a hard winter. Where I am on the edges of North Wales I have several self-sown antirrhinums which have survived the past couple of winters.

If you are thinking ahead then start choosing your Sweet Peas ready to sow later in the year.