The thyme is right to be planting a herb garden
In this extract from their latest gardening book, Kenneth Cox and Caroline Beaton share their passion for herbs, which are easy to grow and taste delicious
May is peak time to plant and sow lots of vegetables but it is also the month to plant herbs, whether you’re growing them in a garden, allotment, raised bed or containers. Kenneth Cox and Caroline Beaton’s Fruit and Vegetables for Scotland is a trove of information for growing edible plants in Scotland’s various soils and microclimates. Here they share advice on starting or diversifying a herb garden.
Scots have used herbs for food and medicine for hundreds of years. Many medieval monasteries had herb gardens and Scots have long gathered wild herbs such as celandine, yarrow, mint, selfheal, henbane and many others for the treatment of illnesses. The Royal Botanic Garden Edinburgh was originally founded in 1670 as a physic garden to produce medicinal herbs.
We must confess a particular fondness for the growing of herbs. Not only did Caroline’s mother and stepfather, who likes to think he is a descendant of the great 16th-century herbalist William Turner, start a culinary herb business in the Carse of Gowrie, her family, the Beatons, were reputed to have been the hereditary doctors to the Lords of the Isles and there is a monument to them at the site of their herb garden on the road to Iona on Mull.
Herbs, annual and perennial, are often planted in a great burst of culinary aspiration and then left to grow on un-harvested, so do consider which herbs you would most like to try growing – that is, what you will honestly use. Next, choose a site for your herbs as close as possible to the kitchen, then at least lethargy won’t stop you harvesting them. Even if you don’t use them for cooking, many herbs add a blousy attractiveness to your garden and many are an excellent food source for bees.
Many herbs are easy to grow and we have seen them thriving in all parts of Scotland, even on an old airstrip on Benbecula. They are rarely troubled by pests and diseases, and they really do need relatively little looking after.
Beyond the traditional herb bed, consider interplanting herbs with flowers or vegetables. Chives and pot marigolds make good companion plants, for example. In the herbaceous border, herbs such as bronze fennel and angelica can add their own particular strengths in structure, colour and aroma. And, if you have no garden at all and only space for window boxes or small containers, then herbs are ideal – contained, beautiful and useful. But do remember to add some soilbased compost and a little grit to your multi-purpose compost. Most herbs grow well under protection too and, for tender ones like basil, indoors is much better than out. Container growing is also a solution to gardens with heavy soil and it means that you can bring your herbs indoors or under some protection over winter. Herbs unhappy in containers are angelica, borage, caraway and sweet cicely.
All herbs can be grown from seed but, as you probably only want one or two of most of them, buying small plants might be a better option. In any case, some herbs, such as parsley, are erratic germinators, so buying plants is a good investment. Annual herbs tend to be sown in situ as they often react badly to transplanting. You may want to succession plant to get several crops throughout the season.
Garden centre chains and DIY sheds will try to sell you herb plants flown in from Spain from March and April onward. These are totally inappropriate for Scotland, with growth too far advanced to plant out in 2018’s late spring. Don’t touch them unless you can keep them going indoors. Most of the independent garden centres know better and won’t make this mistake, we’d like to think. Wait to plant these out until well into May for milder and coastal gardens and further beyond for colder gardens. Gradually harden off herbs before planting out. Many perennial herbs are quite easy to propagate from cuttings, division or layering. Some commonly used herbs have both a medicinal and a culinary profile. Note that one or two common culinary herbs can be harmful if used excessively – for example, parsley is potentially damaging to the liver and pennyroyal is not recommended during pregnancy.
Site, soil, sowing and planting
For herb seed germination, a little bottom heat will work wonders if you can provide it. The majority of herbs enjoy a light, gritty, free-draining soil. Herbs less fussy and more amenable to heavier soils include caraway, chives, horseradish, lemon balm, lovage, mint, salad burnet and sorrel. Almost all herbs like a good deal of sun. The exceptions, that can be grown in semi-shade, are angelica, chervil, horseradish, lovage, mint, parsley, salad burnet, sorrel and sweet cicely.
As ever, keep your plants weeded. Once established, most are quite drought tolerant. You’ll get a much longer cropping season if you can protect herbs from frost in autumn. Remember to pay attention to feeding and watering container-grown herbs and protect their roots from frost. Bay and rosemary have particularly frostsensitive roots and are often killed in containers in cold winters.
Harvesting, storage and seeds
To store leaves, freeze them, chopped, in ice-cube trays to which a little water has been added, packing the resultant cubes in freezer bags. Or just
Choose a site for your herbs as close as possible to the kitchen, then at least lethargy won’t stop you harvesting them
freeze them as they are. Don’t mix different herbs in the one bag. They will last for up to six months, with flavour and colour diminishing considerably after this and defrosted they are really only fit for adding to sauces and stews. You could also try storing herbs by making flavoured oils and vinegars with some. Try tarragon or rosemary.
To gather the seeds to use in the kitchen, wait until you can see the seeds loosening or falling from the flower heads. Cut the heads and place upside down in paper bags. Label and leave in a warm place to dry. Shake the seeds into the bag and then remove any debris and transfer to an airtight jar. Keep in a dark place, such as your kitchen cupboard. To store them for future sowing, keep them dry and cool. The fridge is ideal if you have space. You can freeze them.
Common problems Long, cold, wet winters are the most common cause of herb failure in Scotland, especially if the herbs are in a heavy soil. For much of Scotland, keeping herbs going for more than a year or two is quite an achievement. Having said that, they are relatively cheap to buy and quick to grow, so regular replanting may not be too much of an issue. For perennials, you can always arrange an insurance policy – take cuttings in late summer and overwinter them in a cold frame. The majority of herbs are unlikely to be troubled by pests and diseases. As a general rule, if you see something untoward, remove the leaves or stem affected and burn. Lift and destroy the entire plant if the whole thing is affected.