Seeds to plant now for cut flowers next summer

Growing flowers from seed will give you great joy and satisfaction

It seems strange, at this time of year, to talk about next summer. But as any seasoned gardener will tell you, that is the nature of the beast; we’re always thinking ahead, always doing our best to nimble-footedly anticipate the seasons yet to come. Which is why now is the time to sow seed of a handful of ultra hardworking, hardy biennials if you want to be able to pick armfuls of their wonderful cut-blooms next year.

But why, you might ask, would you bother growing flowers for cutting when they can be so easily bought from your local florist? Well, I could bang on for hours about the many reasons – some ethical, some environmental, some reflective of a deep-rooted desire for ‘slow’, seasonal, organic, scented blooms expressive of the Irish gardening year – as to why it’s so worth it. But I won’t. Suffice it to say that doing so will give you great joy and satisfaction.

To those who say that their gardens are too small, my answer is that you’ll be amazed by what you can squeeze into a few square metres of good soil. And even if your garden is truly tiny, there are other clever solutions, such as taking on an allotment with a couple of like-minded gardening friends, or perhaps joining a community garden with a view to establishing a few beds for cut-flower growing. So don’t let lack of space deter you.

Instead let’s talk about what to sow now. Sweet William (Dianthus barbatus) always comes top of my list as one of those exceptionally robust, easy-to-grow, old-fashioned biennials that’s easy to raise from seed. Its intensely perfumed flowers, which appear on 45cm-long, strong stems from late May-July, come in a wide range of colours, from the darkest scarlet to the purest snow-white. All are exceptionally long lasting in a vase, staying the pace for as much as two to three weeks.


[CROSSHEAD]Sunny spot[/CROSSHEAD] In particular, look out for Dianthus ‘Sooty’ (crimson-black flowers), white-flowering D. ‘Alba’, D. ‘Oeschenberg’ (dark foliage and purple flowers) and D. ‘Auricula-Eyed Mix’ (flowers in varying hues, each with its own distinctive, pale ‘eye’). Sow the seed now, either directly into a well-prepared seedbed outdoors or into seed trays. Thin/ transplant the young seedlings to 15cm apart/into cell inserts, and then plant them into their final positions in October, making sure to give them a sunny spot in fertile, moist, but well-drained soil.

Also always on my list of summer-sown biennials are foxgloves, including Digitalis ‘Apricot’, which produces its elegant flower spikes in a delicious shade of coral-peach. Foxglove seed is minuscule, meaning that it’s easy to sow it too thickly or too deeply, or even to lose it by sowing on a windy day, or watering too heavily. So while you can sow outdoors into a well-prepared seedbed, I prefer to sow into pots, onto the surface of damp compost, before covering it with a layer of cling film, leaving enough space for the tiny seedlings to germinate. I then prick these out into cells/individual modules before transplanting them into their final position in autumn.

Yet another early summer-flowering biennial that makes a great cut-flower is the deeply-scented Sweet Rocket (Hesperis matronalis). [CROSSHEAD]Resilient[/CROSSHEAD] Both the common violet-flowered form and the pretty white Hesperis matronalis ‘Alba’, can be easily raised from seed surface-sown now, either into a well-prepared seedbed or alternatively into seed trays/pots filled with compost. Again, these seedlings should be thinned/pricked out, so that the adult plants are spaced roughly 30cm apart. A surprisingly resilient plant, Sweet rocket will tolerate a certain degree of shade but is happiest in moist, fertile soil and full sun.

The same is true of honesty (Lunaria annua), a cottage garden favourite and late spring flowering biennial easily raised from seed direct-sown in June/July. Among my favourite varieties are Lunaria annua var. alba (white flowers), L. ‘Corfu’ (violet-blue flowers) and L. ‘Chedglow’ (chocolate-coloured leaves and dark-purple flowers). Cheeringly, the pretty flowers are followed by stiff, papery discs, which are highly ornamental in their own right.

And let’s not forget the biennial wallflower; this month I’ll be sowing seed of several different varieties, including the pretty Erysimum ‘Giant Pink’.

Last but certainly not least is the Iceland poppy (Papaver nudicaule). In particular, I’m a huge fan of the strain known as ‘Champagne Bubbles’, which produces its large yet ethereally graceful flowers on 40-50cm long stems, with paper-thin, crumpled petals in shades of orange, yellow, white and coral. Amazingly for a poppy, those papery blooms last very well in a vase. As for propagating it, most books and websites will tell you to direct-sow its tiny seed, but ignore them. Far better to surface-sow now into a pot or seed tray filled with damp compost, then cover with cling film until you see signs of germination. Once the individual seedlings are large enough to handle, prick these out into cell trays before transplanting into their final position in autumn. You’ll have to protect the young plants from slugs, but the resulting flowers are so drop-dead gorgeous that you’ll be glad you did.

Recommended specialist online seed suppliers include,, and