Autumn-sowing Hardy annuals

Hardy annuals are the bedrock of the cutting garden. I am growing more and more perennials (for sustainability) but I cannot and will not ever give up on having hardy annuals. They are embarrassingly easy to grow, endlessly generous, and absolutely gorgeous.

Hardy just means they aren’t phased by cold and will even do better if they are sitting in the soil over winter (they will spend that time putting down a great root system). Annual means they will flower within a year of sowing the seed. Instant gratification by another name.

My absolute favourite hardy annuals for cutting

/ White corncockles

/ Borage

/ Bishops flower (Ammi majus)

/ Love in a mist

/ Cornflowers

/ Opium poppies

/ Mixed scabious

/ Orlaya

/ Ammi majus

/ All the nigellas

/ Larkspur

/ Bupleurum

/ Briza maxima

/ Omphalodes linifolia

/ Bladder campion

When to sow

Hardy annuals (plants that are not killed by frost) have two options. They can germinate, grow, flower, set seed and die all in one season, or they can germinate, and grow in the autumn of one season, and then flower earlier the next year.

If you want to get everything in one year, sow between March and May. Don’t rely on the calendar date to know when to sow though; use your senses. The air will smell different, the weeds will germinate rapidly, absolutely everything will be growing.

If you would like them to over-winter, sow in late August or very early September. Sowing before then means that they get a bit ’stuck’ between the options, and will panic as the cold weather comes in. You will end up with some short, not very happy looking flowers in November. Sowing too late and the cold will overtake then and the plants won’t be big enough to make it through the winter.

Obviously, you can do both. It’s not greedy.

Successional sowing (sowing little and after in a staggered way) will give you the longest season of colour and joy. Every few weeks, if you can manage it, will give you all the flowers you will ever need, and some to give away.

Where to sow

If you have warm soil and lots of space, direct sowing is quick and easy. My one top tip on this would be to make sure you have hoed the soil; seeds will really struggled in lumpy, rough textured soil.

Most annuals are energy-hungry because they grow and flower so quickly, so put in full sun and good soil. (You’ll probably have to feed too.)

How to sow under cover

You will need:

/ Peat-free seed compost

/ Small pots or module trays

/ Labels

/ Seed

Fill a tray or your pots with compost. Shake and pat to level a bit but do not compact the soil. Aim for the texture of a Victoria sponge.

For larger seeds, poke two seeds half a centimetre below the surface of the compost. For tiny seeds, just scatter a pinch in each cell.

Cover with vermiculite or a thin layer of seed compost and then put the pot or tray in water for half an hour to water from below.

Place in a warm spot. If you have a heat mat or a windowsill propagator, all the better.

Some seeds will do best if you cover them with a compost bag and germinate them in darkness, some really don’t like that at all so do a bit of research on each variety.

Keep the compost moist but not wet. Let the surface of the compost dry out between waterings, it shouldn’t always be dark.

Once seeds have sprouted, wait until two pairs of leaves form. Carefully pot up each seedling into a pot filled with sieved compost.

You can plant out in the autumn if the soil is still warm or, if you were a little bit late and have been caught out by the cold, over-winter them in a greenhouse and plant out as the soil warms in the spring.

Cutting your gorgeous flowers

Autumn-sown annuals will be up and out by the end of May. Harvest little and often. Enjoy.