Growing food from seeds is one of the wonders of gardening and often taken for granted, but it is definitely one of the most exciting and even addictive activities around. Browsing seed catalogues early in the year I always feel I am spoilt for choice.
The Organic Gardening Catalogue, for example, lists more than 50 varieties of tomatoes; The Organic Centre’s seed catalogue offers more than 50 varieties of lettuce from Butterhead to Cos Lettuce and Loose Leaf Type to Oriental Greens; Thompson and Morgan and Mr Middleton have 20 different carrot seeds in their programme, including Autumn King and ‘Healthy Coloured Carrots’, specially selected for their health benefits when eaten raw.
You might also want to grow unusual vegetables that are expensive to buy or hard to get like Kohlrabi, champion pumpkin, yellow courgettes or Barlotta beans.
This year, I’m planning to try sweet potatoes in the polytunnel. The Organic Gardening Catalogue offers root cuttings or ‘slips’, which should be put in water for a few days to revive before planting. I will compare these root cuttings with slips I will cut from sweet potatoes bought at the farmers market. I will plant them in April. If you don’t have enough spaces you could try planting in big containers or in fish boxes.
Seeds must be viable and of good quality and not too old. Most seeds store for two to four years in a cool, dry place, but I tend to use new seeds every year.
I use organic seeds, which are harvested from organically grown plants and are not treated with any chemicals for controlling fungi, storage pests and other diseases. But I do compromise occasionally and use non-organic seeds – for example, Sungold tomatoes – if they are not available as organic. At home, we treat tomato and cucumber seeds with Valerian extract, to strengthen them before sowing.
The best temperature for most seeds to germinate is 16-20°C, and there are different types of heated propagation units available with heating pads or mats with thermostat or soil warming cables.
Beware of damp off
Seeds need moisture and air to germinate, but beware of ‘damp off’ caused by overcrowding and overwatering. Prick out seedlings as soon as the first pair of true leaves appear, so that each has more room. Increase air circulation by removing propagation covers on sunny days, and water from below, as this keeps the soil surface drier.
Once germination has occurred, all plants require light, ideally from above. Germination on window sills works only to a degree, and plants often become leggy. Note: A few vegetable seeds require light to germinate, e.g. lettuce, celery, they need to be sown shallow.
When to sow
Sowing and planting outside too early is the most common mistake. Don’t be fooled by lovely spring days in March. They are always followed by a cold spell. The only seeds I sow outdoors in late March and April are broad beans, peas, potatoes and onions.
I raise most other vegetables in modular trays and pots and plant them out in May. Carrots and beetroot are probably the only seeds I sow directly outdoors from May on. The seedlings can then be transplanted from modular or cell trays into the prepared bed or potted on into bigger pots for another two to four weeks. This process has an added advantage: Those well-established small plants are more resistant to the bane of the gardener’s life – slug attacks.
‘Garden to table’ series
Watch out for Hans’s ‘Garden to Table’ articles, which will run every four weeks, starting on March 8.
There will be ten articles in the series, with each covering a different edible plant – how to grow it and a recipe suggestion. Each article will carry a small token – collect six of these and receive a surprise selection of seed packets. Simply send your six tokens to Garden to Table, The Mayo News, The Fairgreen, Westport, Co Mayo.
Hans Wieland is joint manager of The Organic Centre, Rossinver, Co Leitrim, which offers courses, training and information in organic growing, and runs an Eco Shop and an online gardening store. For more information, visit www.theorganiccentre.ie, e-mail firstname.lastname@example.org or phone
071 9854338.Contact Hans at email@example.com.