Beware the risks of spring

HOME GROWN:ONE OF THE hardest things about growing vegetables is holding back from planting them too early. The sun is shining, the birds are singing, and green shoots are sprouting all over the garden. And surely that is the sound of the vegetable patch crying out to be filled with good things to eat? On the contrary, that is more likely to be the siren song of our fickle Irish spring. The air may be warm during the day, but the soil is still cold, and frost may hit at night.

Old-fashioned gardeners had strict ideas about when to sow seed or plant things into the soil. Last frost dates dictated when it was safe to plant out tender veg such as runner beans and courgettes. May 1st, May 15th and May 31st were the magic dates depending on whether the area was mild, moderate or cold. In really chilly areas, they knew that frost was still possible into June. But in recent years we have had such mild winters – until the past season – that frost dates were forgotten. Gardeners took chances, and often suffered no ill consequences.

This winter has been a different matter altogether: the soil has been slow to warm up, and more frost is a definite possibility. So, although you may see vegetable plants for sale in garden centres, hold off for a little while, unless you are lucky enough to have a polytunnel or large greenhouse. Instead, why not think about starting some seeds? (See the list below for suggestions.)

SOW YOUR OWN

Buy special seed compost, or make your own blend. I use sieved peat-free compost and enough horticultural sand to make the mix scrunch in my hand (about 25 to 50 per cent of the total volume).

Large seeds, such as those of beans and courgettes, can be sown in small pots. For others, use seed trays (bought, or home-made ones fashioned out of plastic food containers into which you have poked drainage holes). Or use seed modules – trays with separate cells for one or two seeds – which make transplanting easier.

Fill the container with compost. Water using a watering can with a fine “rose” (perforated nozzle), so that the mixture is nicely damp rather than heavily sodden. Some gardeners like to place the container in water and let moisture soak in from below, but I find this time-consuming. It can also lead to too-soggy compost.

Sow the seeds sparingly, and cover with compost: follow the directions on the seed packet regarding the correct depth. Small seeds can run out of steam if sown too deeply. I cover the surface of the compost with a very thin layer of coarse sand: this helps retain moisture, prevents algae from forming, and deters fungus flies. Water again (lightly) if necessary, and put the container into a propagator, or into a clear polythene bag with some air space at the top. This creates a moist atmosphere, which promotes germination.

If the seeds need heat, and if you don’t have a heated propagation set-up, place near a radiator, or somewhere warm (my seedlings are all germinated on a high bench over the radiator by the kitchen window). If necessary, move them to a bright spot as soon as they sprout, so that the seedlings don’t get drawn out looking for the light. Be aware though that seedlings can cook inside a polythene bag if they are in a hot, bright conservatory.

Water only when the compost is nearly dry (which may take a week or more, if the container is covered). When the seedlings have grown a set or two of leaves they are ready to be potted on into larger containers. Keep the roots as intact as possible when you handle them.

SPROUTING SUCCESS

If you can’t provide good light after germination, delay sowing until the days are brighter.

Seeds that are sown too closely may fall foul of “damping off disease”, a fungal disorder where the seedlings go limp and collapse.

Never water seedlings if the compost is already moist

Make sure that all your seed-raising equipment is squeaky clean, and that you use fresh compost. Seedlings are vulnerable to pathogens.

Seaweed extract (available from garden centres) helps with root formation: use as directed on the label.

SOW NOW

Sow inside with heat: courgette, pepper, tomato, basil and other herbs.

Sow in containers in greenhouse or cold frame, or in an unheated conservatory or porch: French and runner beans, Brussels sprouts, onion (seed), salad leaves.

Sow outdoors directly into soil or under cover (as above) in containers: broadbean, summer cabbage, winter cabbage, calabrese, leek, pea, spinach, Swiss chard.

Sow outdoors directly into soil: early and maincrop potatoes, beetroot, parsnip, onion sets, radish, spring onion, turnip.

Irish vegetables for Irish gardeners

The Irish Gardener's Handbookby Michael Brenock (O'Brien Press, €9.99) is a practical paperback aimed at those growing their own food on this island. The author previously worked for Teagasc developing commercial vegetable growing, so he knows his onions.