Yellow Rattle and Wildflowers - What do I sow and when?

If, like me, you would like to diversify and make a little space for more native wildflowers then autumn is a good time to sow many perennial wildflowers.

Have you heard about Yellow Rattle or ‘Meadow Maker’?

This is an annual that grows best from fresh seed sown in the autumn. It is usually available as fresh seed from late August. The seed then needs light and a period of cold stratification for them to germinate which will happen in the spring producing flowers in early summer. It is popular because it uses nutrients from grass and this stops the grass from being too dominant in the meadow and allowing other annuals and perennials to flourish.

Yellow rattle is a meadow plant so tolerates quite moist winters but dislikes drought in the summer. To encourage the setting and dispersal of seed a later summer mowing of hay will help to disperse the seeds to germinate the following year.

How do I sow my Yellow Rattle?

When buying and sowing yellow rattle make sure the ground is prepared usually by raking the area to remove much of the grass thatch and disturb any compacted soil. Sow over the area and then tread down to enable the seed to make contact with the soil.  The Yellow Rattle needs the remaining grass roots for nutrients as it is semi-parasitic on grass, so do not clear the ground completely but reduce the grass coverage by about half.

For more detailed advice see our information sheet on How to Sow Yellow Rattle https://justseed.com/pages/how-to-grow-yellow-rattle-from-seed

What do I need to know about cold stratification?

Cold stratification is the process by which some varieties recognise when it is good to germinate. They require a period of cold weather to prime the seed before germinating  when the temperature becomes warmer and more favourable to germination.

Perennial wildflowers

The following are guidelines only! As many wildflowers sow themselves in the wild and will drop their seed over a period it is useful to know those that prefer a particular time of year. However they also may be quite forgiving as to when they are sown. The principle ones are those that need cold spells to be sown in the autumn which includes many of the perennial wildflowers.

Best Sown Autumn:

Many of the perennial wildflowers are best sown in autumn. Some will germinate and then establish a good root system while others need cold to facilitate germination.

Betony, Cowslip, Oxlip, Common Primrose, Common Agrimony, Kidney Vetch and Lady’s Bedstraw, Rough Hawkbit and Salad Burnet, Devil’s Bit Scabious, Field Scabious (Knautia)

Bulbous Perennials: 

English bluebells like a moist soil and a period of cold to germinate. The same applies to Ramsons (Wild Garlic) and orchids. Many of the wildflowers which produce rhizomes or bulbs will take a long time to come to maturity meaning they may not flower until 5 years or more after sowing. It is worth sowing these in pots and labelling well so that you can identify when your seeds have germinated.

Sow Autumn or Early Spring:

Self Heal, Yarrow, Knapweeds, Field Scabious, Cow Parsley, Common Toadflax, Fritillary, 

Best Sown Spring:

Evening Primrose, Purple Loosestrife, White Campion, Wild Marjoram, Nettle Leaved Bellflower, Ragged Robin

Wildflowers are not an exact science in terms of germination and there are some differences of opinion. Sow some of your seed if you can in autumn and keep some back for the spring. You then have two chances of getting them to germinate!