sweet peaHow do I grow hardy annuals?

Add hardy annuals such as cornflowers and poppies into your garden for quick and vibrant colour. They are easy to sow directly into the soil, inexpensive, and provide you with colour the same year if sown in spring, or the following year if sown in autumn.

What can they do for me?

Hardy annuals are great space-fillers among shrubs or look great in their own right. You can even consider growing them in containers.

  • Keep displays interesting
  • Grow flowers for cutting
  • Provide a theme in the border
  • Make use of annual climbers

What are hardy annuals?

A hardy annual is one you can sow outdoors in the UK, which germinates from seed, grows, flowers, disperses its seeds and dies in one growing season. (All in the same year if sown in spring, or from one autumn to the next).

There are myriad hardy annuals which you can peruse in garden catalogues and nurseries. Here is a list of favourites to choose from:

  • Cornflower
  • Honeywort (Cerinthe)
  • Nasturtium (Tropaeolum)
  • Sunflower (Helianthus annus)
  • Love-in-a-mist (Nigella)
  • Californian poppy (Eschscholzia californica)
  • Sweet pea (Lathyrus odoratus)

watering seedsHow do I sow them? 

  1. In spring or autumn, prepare the ground for seeds - remove large stones and rake the soil so the level is even and there is a crumbly surface known as a tilth. Do this on a dry day to avoid compacting the wet soil.
  2. Decide whether you want flowers of one kind to be in blocks or scattered throughout the bed. If in blocks mark out shallow grooves in the soil using the corner of the hoe in arcs.
  3. If scattered, simply scatter seeds thinly all over the area - this is known as ‘broadcast sowing’. Keep the seed packet because once the seed germinates it will offer essential information about aftercare. If sowing in blocks, add seeds in the grooves at a distance advised on the seed packet. Cover the grooves over with surrounding soil and firm it. This can be done using the edge of a rake.
  4. Mark the area with a plant label for future reference and for good planning.
  5. Water the area with a watering can with a sprinkling head (rose) so the water does not splash the seeds out of soil.
  6. When the seeds germinate and the seedlings appear you may need to get rid of some seedlings to provide space, light and nutrients for the remaining seedlings. Seed packets will advise you what the spacing requirements of seedlings are. When removing seedlings do so carefully so you don’t disturb the roots of the seedlings you are keeping in the soil. Water the seedlings according to the weather. More on watering

What else can I find out about sowing seeds in my garden?

More on sowing in autumn
Sowing vegetables

Other links

Come and see the impressive hardy annual displays and bedding schemes at the four RHS Gardens where you can get inspiration on planting a whole host of annuals.

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