Unwins Seeds

How to Sow Hardy Annuals Outside

05 September 2014 | Posted in Gardening by The Unwins Family

How to Sow Hardy Annuals Outside

Autumn may feel chilly to us after the warmth of summer but soil is still warm and the season also promises abundant rain. This is the perfect combination for sowing seed of hardy annuals.

When it comes to flowers October and November are usually the last months that you’ll get away with sowing seed outside, but a sowing of hardy annuals in September is always worthwhile because hardy annuals germinate best in cooler temperatures. They’ll make sturdy plants by next spring and flower earlier than spring sown seeds.

Annual plants complete their lifecycle quickly; they make all their growth including flowering and setting seed in one year. There are hardy and half hardy annuals. Hardy annuals will tolerate a frost and they’ll cope with cold winter weather so they are the ones to sow now. In the catalogue and online these are marked as Hardy Annuals (HA). Unwins seed packets also indicate which are suitable to Direct Sow in autumn.

When you buy seeds from Unwins you can be certain they’ve been tested for performance and of course each seed packet has full instructions and helpful aftercare tips.

Direct sowing outside

Sowing seed directly outside is an easy and cost effective way to get a natural looking display of flowers, especially if you have a large area to fill. You can just scatter seed randomly, especially if you choose an easy seed mix such as Nature’s Haven Easy wildflowers  or Gro-sure Easy Flower mixes.

But if you want drifts of different varieties the best way of sowing is to mark out an area for each variety and sow into it.

Whatever you’re growing, whether it’s hardy flowering annuals or a collection of hardy herbs or salads the method for direct sowing outside is the same. It is also very simple; you won’t need special tools, just a rake, a hand fork and some plant labels, and a watering can.


1 First prepare the area by getting rid of weeds and removing any large stones then rake the soil so it is level and crumbly (often described as a ‘fine tilth’).

2 Mark out an area in the soil for each different seed variety.  They can be sown in lines, blocks or circles but sowing in overlapping drifts produces a very natural effect.

3 Mark out ‘drills’ - shallow depressions within each area, where you’ll sow the seed. You can make them with the tip of the rake or a bamboo cane.

4 Sprinkle the seed very finely along the drills; sow the seed thinly because seedlings will need space to grow and mature.

5 cover it over very lightly with soil when the seed is sown; you can do this with your hands or a hand fork or by raking it gently along the drill, then and add a plant label- (It’s easy to forget what you’ve sown if you miss out this step!)

6 Finally, water the length of the drill; use a watering can fitted with a fine spray or a sprinkle bar to avoid washing the seed out of the ground.


To mark out areas like the professionals fill a drinks bottle with sand and trickle the sand slowly from the bottle to mark out different areas for each seed variety.

Unless you have a large space to fill you will only need a small amount of seed so don’t be tempted to sow the whole packet into one small space!

If cats or foxes are a problem in your area cover the soil after sowing with mesh or fleece; or put down a few rose prunings or holly stems to deter animals from disturbing the area while your seeds are germinating.

After care

Keep the area watered in dry spells; but don’t saturate the soil.

Germination will take place within a week or two, depending on the weather, and you’ll see the first true leaves appearing. (Embryonic seed leaves, called cotyledon, appear first followed by the plants true leaves).

Thin out any congested clumps if necessary, leaving space around each stem so seedlings don’t have to compete with neighbours that are too close.

TIP Don’t weed ANYTHING until you are certain which are your precious seedlings and which are weeds!


Make A Comment

You need to be a registered user to submit comments. Login or register.


Sign Up for our FREE newsletter - Full of great tips and offers

By submitting your email address in the box below, you agree that Unwins may send you special offers about their products and services by email in the future