My garden froze in mid-January but down came the rain to return it to mud. Even I regard outdoor gardening as a lost cause when a British January throws this combination at it. So I have looked forward, a gardener’s great resource, and set about planning this year’s seed sowing. I recommend it. The darkness has dissipated as my aims outran my seed boxes. Gardening is not just shopping: seed sowing puts the -ing back into gardening.

I divide sowing for the summer into two: seeds of hardy annuals, which go easily and directly into open ground from late March onwards, and seeds of half-hardy annuals, which need to be started into growth in a warm cupboard or glasshouse, usually in mid to late February. If you opt to use a cupboard, remember that you must take the germinated seedlings out into frost-free daylight as soon as their green tips show. If you leave them in the dark for a day too long they become spindly and elongated and never recover.

I like to buy both types of seed at once, while my mind is integrating them into a summer plan and before others have bought all the hardy varieties on display in racks in garden centres. My two types have just become three, thanks to a timely circular from a frontline grower, Derry Watkins of Special Plants Nursery in Cold Ashton near Chippenham, Wiltshire. It is one for keen gardeners and though it is specialised it is not difficult to satisfy.

From experience, Watkins has learnt what I had not fully grasped, that seeds of some of the boldest and most popular categories of border plant need to be sown and stood outdoors while winter persists. They need to be sown while the seed is still fresh, spring to summer sowings being too late. Watkins singles out seeds of many umbellifers, those impressive border plants which mostly have flat heads of flower, increasingly popular with designers.

She offers packets, a few, of good angelicas and a bold plant, Seseli gummiferum, which is white-flowered and grows up to 3ft high. She well calls it “the queen of umbels”, though it dies after flowering a few years into its lifespan. She also offers seeds of the vivid red Anemone pavonina, a fine sight in Greece in spring, a classy dark red astrantia called Bury Court and a new sort of cimicifuga, found in the Chinese province of Hubei by the celebrated seed collector Dan Hinkley. On April 11 she will be running a day course at her nursery entitled Sowing Seeds. Places at £60 each are limited but still bookable at specialplants.net.

My two other divisions are for everyone, novice and expert alike. I begin by visiting nearby garden centres to buy what catches my eye on their racks of seed packets, but I know that these sources are only indicative. The major suppliers on display include Thompson & Morgan, Johnsons and Mr Fothergills, but each has much fuller catalogues online. On a dark wet Sunday I like to shop on impulse, so here are some of my choices this year from those awaiting impulse buyers.

Sweet peas are essential and can usefully be started promptly indoors or under glass. I bagged a packet of Thompson & Morgan’s Flying the Flag simply because I liked its mixed colours of red, white and blue sweet peas and the promise of exceptional scent. Sweet pea seeds should be soaked in water for a full day before sowing as the water softens their hard coating.

I will match this patriotic mixture with two pillars of my summer garden, Thompson & Morgan’s King Size Navy Blue, still the best of the dark blues, and April in Paris, off-white edged with pale mauve, which I like because of its evocative name, its scent, its long season and freedom of flower. My packet comes from Johnsons with a picture of designer Sarah Raven on it too and an endorsement by her which tells us that April in Paris’s flowers remind her “of delicate Venetian marbled paper”. I think of them as slightly flushed with mauve and I do not see this marbling.

Last year’s wet summer did wonders for the height and strength of my mainstays, tall white-flowered Cosmos Purity, a much better choice than the lower-growing Sonata. I usually add some of the glowing red Cosmos Rubenza, an excellent plant for gaps in a mixed border. The flowers fade to rose red but they keep on appearing well into autumn. For Johnsons again, Raven has endorsed Cosmos Dazzler, a deep carmine pink which she credits with “brilliant vase life”, a feature on which she is an expert. Dazzler too is tall and as it was to hand, I bought it, reckoning to email later for Rubenza.

Among Afro-French marigolds, Marigold Konstance from Thompson & Morgan remains my first choice, a superb one in all weathers and a refutation of those who keep marigolds out of their garden because they think they will be heavy headed and orange flowered. On impulse I added their Marigold Colossus (French), a long-flowering variety, bi-coloured in red and orange and “the largest French marigold,” with flowers “larger than a golf ball”. It sounds as good as a hole in one, and I love marigolds anyway, as do many gardeners, public and private, in Pakistan and India.  

Happily, I found and bagged seeds of low-growing Phacelia campanularia from the Johnsons-Raven combo, a wonderful deep blue-flowered hardy annual for all but the hottest summers. I decided to try Poppy Royal Wedding, “the pick of the bunch”, from Thompson & Morgan, white with a dark centre, and their Calendula Snow Princess, with “flowers in 10 weeks from sowing” directly outdoors and “a world first” in creamy white pot marigolds. As an experiment, I added low-growing Alyssum Oriental Nights whose heads of small lilac-purple flowers “are ideal for honey-scented table centre pots”, to Raven’s ingenious eye.

You were playing safe, hardened gardeners may be thinking: indeed, but I like sure results from off-the-cuff shopping. For a wider, rarer range try Plant World Seeds in Devon, whose list contains more than 3,500 varieties of flower and vegetable seeds. The prices are lower than most of the packets in garden centres, let alone those stamped with approval by the RHS. Plant World lists anything from unusual Chilean argemones, with big primrose yellow flowers like poppies, to Ammobium alatum, a winged everlasting white flower with a raised yellow centre, excellent for cutting and enjoying for weeks indoors. Fabulous blue Himalayan poppies, including seed from the selected Lingholm strain, are also on sale with clear instructions on germinating them.

In May, we will be buying yellow-flowered bidens by the dozen to fill in pots and window-boxes, often at £3 a plant. Plant World offers a big packet of seeds of Bidens Golden Nuggets for only £1.95, with invaluable advice that the seed, to be sown in heat in April, must not be covered in its bed of sharp compost. Fifty plants or more come to a base cost of £1.95 plus heating at your control, whereas one plant, potted, will cost £3. This start-up is too good to miss. With seedlings there is always an assured exit.   

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Source: ft.com