The pot of parsley by the back door has begun to run up to flower. It's the reminder I needed to sow a fresh supply. Parsley by nature is a biennial. You sow it one summer and can crop it through until the same time the following year. In the second summer, you can cut off the flowering stems, but you can't hold the plants back for long. At this stage, they are programmed to set seed, not produce leaves.
Laziness is the chief reason I sow parsley in a biggish pot (30cm across) by the back door. I don't want to be stumbling around with a torch at night to retrieve it from some further part of the garden. I know, I know. I should pick it before it gets dark. But then, if I was blessed with foresight, I would have sown my new crop of parsley last month, before the present plants went up to seed.
The parsley I've been cropping over the last year is 'Moss Curled' (Marshalls £1.45). This year I'm sowing 'Laura' (Thompson & Morgan £1.99), a flat-leaved, so-called 'French' parsley. Fancy cooks say it has a better flavour, but for garnishing, it's not so pretty as the curled kind. Ideally I'd have both, but on the stone ledge by the back door, there's not room for more than one container.
To grow a crop of parsley, fill a pot three-quarters full with your own compost – if you've got it – before adding the multi-purpose stuff. Then water the pot thoroughly and scatter the seed as thinly as you can before topping off with a thin layer of more compost. Water again, using a fine rose, so the seed doesn't get washed about. Then wait. Parsley takes a long time to germinate, six weeks sometimes. Don't let the pot dry out. Once the parsley starts to grow, all you have to do is water it, adding an occasional feed of something nutritious. I use Vitax Organic Liquid Seaweed.
Parsley, rich as health addicts know, in iron as well as vitamin C, is unusual in choosing to grow as a biennial. Most other common herbs are either shrubby (like sage), perennial (like mint) or annual (like coriander). All can be grown easily in pots. For the shrubby kinds of herb such as sage, all you need to do is buy a small specimen at your local garden centre, plant it, then watch it grow into a much bigger one. Many of our most common herbs – chervil, chives, fennel, parsley, rosemary, sage and thyme – came to us with the Romans. Though they will grow here without too much trouble, they are not true natives.
In a pot, the most likely problem for rosemary, sage and thyme will be too much dampness round the root in winter. When you are planting, mix plenty of grit in with the compost. For Mediterranean herbs in pots, I use a basic mix of two scoops John Innes No 3 with one scoop of 6mm grit.
To keep sage in good shape and encourage it to produce plenty of leafage, you need to clip plants over in spring and, if necessary, again in late summer. Don't cut deep into old wood. It won't sprout. Clipping in spring means you get very few of the lippy blue flowers, but with a plant that you are cropping primarily for the kitchen, I don't think that matters. You can plant other sage bushes elsewhere for their looks. The purple-leaved sage Salvia officinalis 'Purpurascens' is a terrific foliage plant, sprawling in the front of a border with the grey leaved dianthus 'Hidcote'.
For my birthday last year, we rented a farmhouse in the grounds of Cetinale, near Siena. The place came with a brilliant cook, who occasionally raided a particularly broad-leaved sage that hung in bushes out of the garden walls. He dipped the leaves in batter and served them up, crispy and totally fantastic, at drinks time. If you want to do the same, look for plants labelled Salvia officinalis broad-leaved. The Herb Nursery (herbnursery.co.uk) in Rutland has it. So does Laurel Farm Herbs (firstname.lastname@example.org) in Suffolk and Waltham Herbs (waltham-herbs.co.uk) in Lincolnshire.
Mint, sage, parsley, thyme and marjoram are the herbs that English cooks used most often to reach for. For the classic French fines herbes omelette, you need parsley, chervil, chives and French tarragon. Chervil, with its aniseed aftertaste, grows as an annual and is an easy herb to grow in a pot, like parsley. You can sow it at intervals, every month between May and August, to ensure a fresh supply all summer. All you need to do is water and feed the pots to encourage the plants to make as much leaf as possible. If they are starved, they'll just run straight up to seed.
Chervil is hardy, unlike basil, so you can expect the last sowings to get through the beginning of winter reasonably well, though growth will come to a standstill. If you have good fresh seed, it will germinate quickly and you can be cutting leaves within six or eight weeks. Take out flowering stems as they appear to encourage the plant to leaf up again. Once it has produced seed, it thinks it has done its job and starts to die back. Keep the pot in a cool, shady place rather than a hot, sunny one.
The herbs I use most are basil and coriander. In Florence Ranson's 1949 book about herbs, published by Penguin, she describes coriander only as a seed-bearing plant. Basil seemed equally unfamiliar. "English people," she writes, "usually find its taste a little too strong for flavouring." Not now they don't. As for coriander, it's presently grown far more widely for its leaves than its seed, though it took our seed companies some while to understand that you needed different seed strains to produce plants with plenty of leaf.
I sowed a first pot of coriander 'Calypso' (Thompson & Morgan £1.99) on 31 March this year. The advantage of this British-bred strain is that the leaves break very low down on the stem so you can cut at least three times before the plant gives up trying to replace what it has lost. You can sow seed through until August, as it germinates quickly, often within a week. If you sow a fresh pot every three weeks, you can be sure of a constant supply. Water and feed regularly. Like chervil, coriander will bolt up into flower if it is short of water.