I once had a neighbour, an amateur builder, who liked to hammer in twice as many nails as necessary to hold a thing together. “Nails,” he would say, banging away, “are your cheapest item.” Out in the garden, the same might be said of seeds. Compared with perennials, trees, evergreens and the rest, seeds are a real bargain. For less than the price of one potted perennial, you have potentially hundreds of plants rattling around in a packet.
Where to plant them
Some gardeners shy away from them. “Too small, too slow, too fiddly,” they say. And yet for every speck-of-dust primula or hard-shelled hellebore seed, there are annual flowers whose seeds are easy to handle and quick to grow. Nothing beautifies bare ground in new beds or fills gaps left by winterkilled perennials as effectively as a scattering of annual seeds; you'd be hard pressed to find plants of any category that deliver such a quantity of colour in such a short time for so little effort. Seeded annuals quickly fill containers, brighten corners of a vegetable garden or climb trellises. And as cut flowers, several seed-raised annuals are without peer. On nursery benches you'll find marigolds and impatiens aplenty, but if you want scarlet runner beans, sweet sultan (Amberboa moschata syn. Centaurea moschata), pot marigolds (Calendula officinalis cvs.) or love-in-a-mist (Nigella damascena), you'll have to shake a packet or two.
How to plant annual seeds
The simplest way to handle annual seeds is to sow them outside, directly where you want them. Hardy annuals (such as sunflowers, sweet peas and nasturtiums) can be seeded two to three weeks before the last frost date; tender annuals (such as rose moss [Portulaca], celosia and marigolds) must wait until a week after. Pick a sunny spot. Turn or otherwise loosen the earth, getting rid of all weeds. Rake to a fine, level surface. Draw out shallow, one-centimetre-deep furrows; then drop in seeds individually, aiming for a distance of three centimetres between them. Cover lightly with no more than five millimetres of soil. As seedlings grow, thin them to 15 centimetres apart. It's not much of a stretch to start seeds a few weeks earlier indoors: fill small pots with soil and set them in front of a sunny window. An indoor start to draw out the season makes sense for tender annuals.
How to - Seeds
Easy annuals to grow from seed
Scatter seeds over blank spots in the garden for summer flowers