Winter is approaching - we've had the first frosts which have blackened the Dahlia foliage and killed off the half-hardy Zinnias. My Cosmos seem to have escaped this fate owing to their height (over 6 ft this year!) and are still in full flower.
Once dahlias have been blackened by frost, it's time to cut them down and either dig them up for storage inside over the winter or to apply a thick mulch to protect them. Annuals which have given up the ghost should be removed and composted and empty beds given a covering of organic matter - compost or manure. It can be left on the soil surface for the worms to drag down and enrich the soil over the winter. Where I have planted out biennials, I just mulch around them.
As an avid watcher of predicted overnight temperatures, I dug up my frost-tender Chrysanthemums before any danger of frost. Late-flowering Chrysanthemums like the elegant 'Avignon Pink' don't start flowering until the end of October and will flower up until Christmas. You can either grow them in pots which can be brought in under cover or plant out over the summer and then carefully dig them up with an intact root ball and place them in large pots in a greenhouse/conservatory or potting shed. I find them really useful additions to fresh Christmas wreaths as they are very long-lasting flowers once cut.
I sowed some hardy '10 week' Stocks and Chinese Forget-me-nots late in June and these are still full of flower, so along with some Borage and Feverfew still in flower, a suprisingly summery jug of flowers can be picked even in November.
Viburnum tinus is a shrub that is overlooked for a lot of the year but come October/November it is flooded in fragrant white flowers. These are invaluable just when the herbs that I use for foliage/filler material in a vase (like Borage, Mint and Feverfew) are coming to an end. The baton is handed to this evergreen shrub for most of my winter flower displays and trimmings look good in a fresh Christmas wreath.
Chelsea week is drawing to an end and this year at the Flower Show, 90% of the flowers in the Floral Marquee have been grown in Britain. Getting flowers with different flowering times such as Tulips, Daffodils, Sweet peas and Alliums to be in peak condition for this week is a herculean effort and you can read more in this excellent post by the Physic Blogger. Marks and Spencer gained a Gold medal for their 'Blooms of the British Isles' exhibit and are selling lovely Chelsea bouquets featuring Stocks, Alchemilla mollis and Allium 'Purple Sensation'. At a price tag of £30 though, you could use that money to buy some annual seed and grow, not just one bouquet, but 2-3 vases full of flowers each week all through the Summer.
So, why not get inspired and try your hand a growing your own British blooms this year? May is a great time to direct sow annual flowers outside and if you sow now, you could be harvesting your own flowers in 8-12 weeks. You just need some spare soil - weed-free, sheltered and in the sun. Just follow the instructions on the back of the seed packets and keep an eye out for slugs. Check out my first Cutting Diary article for more information.
This time last month, I had just planted out my first batch of hardy annuals in one of the 3 raised beds in my cutting garden. They're putting on growth quickly now and I'm eagerly anticipating flowers in about 3 weeks. That's Cornflowers, Amberboa muricata 'Sweet Sultan', Malope trifida 'Vulcan', Ammi majus, Bupleurum rotundifolium, Larkspur 'Stock flowered mix', Lupinus 'Snow Pixie' and Orlaya grandiflora. I am just hardening off a second sowing of Ammi and Bupleurum which I sowed due to poor germination the first time. I'll plant them at the end of this week and they'll soon catch up with the first batch.
My half-hardy annuals (Cosmos, Sunflowers, Zinnias, Carnations, Chrysanthemums and Panicum grasses) are all a good size and have been moved from the house into the potting shed so I have clear window sills for a change). I've pinched out the growing tips on the Cosmos, Sunflowers and Zinnias to prevent them getting too leggy and to produce sturdier plants. I will start hardening these off next week for planting out at the end of the month when I can be sure that all danger of a late frost is over.
Even though the plants in my first bed are still fairly small, I have already added individual stakes for the taller annuals - a mix of bamboo canes, birch branches and rustic metal hoops. When the plants grow taller, I will tie them in with jute twine. It is best to stake sooner rather than later as firstly you won't damage established root systems when pushing in the stakes and if you leave it too late you may find that a Summer wind can quickly snap the stems of tall plants like Cornflowers and Cosmos. The removable chicken wire mesh frame will add a small degree of support for the plants (it's at a height of about 15 cm above the soil) but it is primarily a cat deterrent. We have our own cats and a lot of neighbourhood cats that see a raised bed and think it would make a nice toilet - sorry if this is too much information, but there's nothing worse than encountering buried treasure when you are planting your seedlings!
I potted up my dahlia tubers in early April, some in large terracotta pots where they will stay and a couple in large plastic pots as they will be transferred into a raised bed when space is freed up at the end of July. Some are already producing leafy growth, but I will keep them in the potting shed until all danger of frost is over, keeping them in the light and in moist compost.
One Dahlia tuber will produce lots of flowers as long as you just keep picking them. This year, I'm growing the lovely dark red, cactus flowered Dahlia 'Nuit d'ete', 'Sam Hopkins' a dark red form, 'Roxy' with a simple, magenta flower and 'Blue Bayou', an anemone flowered form with lavender outer petals and deep purple pin-cushion centres.
I will be planting 2 Dahlias in the raised bed that is currently home to my half-hardy annuals which will flower from June-July. In this way, this one raised bed will have housed 3 separate crops from February until October/November - first, early flowering bulbs - Daffodils & Iris reticulata, followed by my first batch of half-hardy annuals, and then the Dahlias, along with Carnations 'Giant Chabaud mixed' (a half-hardy perennial which can be treated as an annual) and Chrysanthemums 'Polar Star' - beautiful tricolour flowers with each white flower having an inner yellow halo surrounding a darker, central cushion.
May and June are good months to sow biennials such as Sweet Williams, Sweet Rocket and Honesty. These will put on growth this year and flower early next Spring. This may all seem a bit of a faff as you have to wait for flowers, but they are all worth growing as they provide flowers early in the season before Spring sown annuals have started flowering. If you let some go up to seed, they will self-seed and you can lift the seedlings and arrange them into orderly rows where you would like them without needing to sow again. I missed the boat last year with mine so will ensure I grow a few of each in the potting shed once I have planted out all the annuals at the end of this month and there is space for some new pots.