How to Grow Parsley from Seed (Petroselinum crispum)

Almost everyone has killed a supermarket pot of parsley. You bring it home, it looks magnificent for four days, and then it collapses from the middle outwards and never recovers. That is not a failure of care. The pot holds thirty or forty seedlings crammed into a plug of peat, each fighting the others for a root run that would comfortably suit exactly one plant. Parsley grown properly — from seed, at the right spacing — is one of the longest-lived and most generous things in the herb bed.

Its botanical name is Petroselinum crispum, and its reputation for being slow and sulky to germinate is both entirely deserved and entirely explainable. This guide covers the reason behind the slow seed and how to work with it, the difference between the curled, flat-leaf and root types, the spacing and feeding that keep a plant productive, and how to keep cutting leaves right through the winter — including what happens in the second year, when the plant has quite different plans from yours.

• Sow March–August outdoors · September under cover for winter pots
• Germinate 14–28 days at 18–22 °C — the slowest seed in the herb bed
• Space 20–25 cm apart · pots at least 15 cm deep for the taproot
• Harvest From 10–12 weeks, then continuously until it flowers in year two

Parsley is a biennial that we all grow as an annual

This single fact explains most of what parsley does. In its first year it builds a rosette of leaves and a fat white taproot. Over winter it sits, more or less untouched by frost. Then in its second spring it uses everything it stored to throw up a flowering stem a metre tall, the leaves turn coarse and bitter, the stems go hollow, and once the seed has set the plant dies. Nothing has gone wrong — that is the whole life plan.

So the practical rule is simple: sow fresh parsley every year, and ideally twice a year. A spring sowing carries you from early summer to the following spring; a late-summer sowing takes over just as the old plants start to bolt. When a plant does run to flower, it is worth leaving one to finish: the umbels are excellent hoverfly food, and the seed is easy to collect if you want to try saving your own.

You will see both "annual" and "biennial" on the packets in our Petroselinum crispum range. They are the same species; the label reflects how the variety is usually grown rather than a botanical difference.

Why parsley takes three weeks to germinate

Parsley seed carries furanocoumarins in its coat — natural germination inhibitors that stop the seed sprouting while it is still sitting on the parent plant or lying in dry ground. They are water-soluble, and they have to be washed out before the embryo will move. That is the whole secret. Parsley is not slow because it is stubborn; it is slow because it is waiting for enough water to have passed through the seed coat to prove that conditions really are wet enough to grow in.

Three things follow from that. First, the drill must stay damp for the entire three or four weeks, not just the first few days — every time it dries out, the leaching stops and the clock effectively resets. Second, soaking the seed for twenty-four hours in warm water, changing the water twice, genuinely speeds things up; sow immediately afterwards while the seed is still swollen. Third, temperature matters: at 18–22 °C you can expect seedlings in two to three weeks, but sown into cold March soil at 8 °C parsley can take six weeks or fail entirely.

A useful old trick is to scatter a few radish seeds along the parsley drill. They germinate in four days, mark the row so you do not hoe it by mistake, and are pulled long before the parsley needs the space. If nothing appears at all, our guides to germinating seeds and why seeds fail to germinate work through the other causes, and seed viability explains why parsley is one of the herbs most worth buying fresh each year.

Sowing parsley, step by step

1. Soak, then sow 1 cm deep Twenty-four hours in warm water, two changes, then straight into damp soil or modules. Parsley needs covering — it is not a light-germinator — but a centimetre is plenty.
2. Keep it damp for the full three weeks This is the step that decides everything. Water the drill before the seed goes in, cover the row with a board or a piece of damp hessian until the first seedlings show, and check it daily in warm weather. Our watering guide covers doing it well rather than often.
3. Never transplant it bare-root Parsley makes a taproot, and a taproot that is broken or bent gives you a stunted plant that bolts early. Sow direct, or use deep modules and plant the whole undisturbed plug. In pots, go at least 15 cm deep — see growing from seed in containers.
4. Thin to 20–25 cm The supermarket pot is the cautionary tale. One plant at 20 cm outproduces ten at 2 cm several times over, and the air between plants keeps the crowns free of rot in autumn. Give it soil with some body to it — our soil preparation guide explains why parsley does better on ground that holds moisture.
5. Sow again in ten weeks Parsley is the classic crop for succession sowing: a spring sowing and a late-summer sowing between them cover the whole year, with neither plant ever pushed past its best.

Curled, flat-leaf — or root parsley?

There is a third type that almost nobody grows any more. Root parsley — Hamburg parsley, var. tuberosum — is the same species bred for a fat parsnip-shaped root instead of leaves. Sow Halblange from April to July, lift it from October, and treat it exactly like a parsnip: it roasts, it goes into stock, and it stores in damp sand alongside the other roots you lift at the same time. The tops are edible too, if a little coarse. It is in the range as root parsley. If you want to avoid the thinning altogether, our seed tapes, seed mats and seed pads have the spacing built in, and there are four organic parsley options across both leaf types.

Cutting, feeding and getting through the winter

Cut the outer stems at the base, never shear the top. Parsley grows from the centre outwards, so taking the oldest stems from the outside leaves the growing point untouched and the plant simply keeps replacing them; shearing across the top removes next month's leaves along with this month's. Take no more than a third at a time and a good plant will crop for eight or nine months. A liquid feed every three weeks through summer keeps the leaves large — see feeding and fertilising.

Parsley is genuinely hardy and will stand outside all winter in most gardens, though it stops growing once light levels drop and slowly gets battered. Two things help: a cloche or a sheet of fleece over the row, which keeps the leaves clean enough to use (our guide to cloches, fleece and cold frames covers the options), or a pot brought onto a cool, bright windowsill — see growing herbs indoors in winter. A sowing made in the first half of September still has time to make a usable plant under cover; it is on the list in what to sow in September, along with everything else tagged for the September sowing window. If the greenhouse border is still occupied by the last melon of the summer, our guide to telling when a watermelon is ripe will settle whether it can come out yet.

One pest deserves a warning, because it surprises people. Parsley is in the carrot family, and carrot root fly will lay on it just as happily as on a carrot, leaving rusty tunnels through the taproot and a plant that wilts for no visible reason. The defences are the same: fine mesh over hoops, or a bed that is not next to last year's carrots — see growing carrots from seed, crop rotation and common garden pests.

Common mistakes

• Letting the seedbed dry out. The single most common reason parsley "never came up". The inhibitors in the seed coat need weeks of steady moisture to wash away.
• Giving up after two weeks. Three to four weeks is normal. Mark the row and leave it alone.
• Splitting a bought pot into individual plants. It tears the taproots. Either pot the whole clump on and treat it as one short-lived plant, or start again from seed.
• Shearing the whole plant. Cut outer stems at the base and the plant keeps going; scalp it and it sulks for a month.
• Expecting a second year of leaves. It is a biennial. Year two is flowers, not dinner — so sow again every spring.

Frequently asked questions

How long does parsley take to germinate?
Two to four weeks at 18–22 °C, and up to six in cold spring soil. Soaking the seed for a day beforehand and keeping the drill constantly damp are the two things that reliably shorten it. The seedlings emerge as a pair of narrow, grassy leaves that look nothing like parsley — the true leaves come a fortnight later.

Can I sow parsley in September?
Yes, unlike most herbs. Sow in the first half of the month, either in a deep pot for a windowsill or in the ground under a cloche, and you will have a usable plant that stands right through to spring. Later than mid-September there is too little light to build a plant before winter, so wait for March.

Why has my parsley gone bitter and thrown up a flower stem?
It has reached its second year, or a young plant was badly checked — a cold snap, a dry spell or a damaged taproot can all convince a first-year plant that it has already been through a winter. Cutting the flower stem out buys a few weeks of poor leaves at best. Sow a replacement instead.

Curled or flat-leaf — which should I grow?
Flat-leaf for flavour and for anything cooked; curled for hardiness, for a long winter crop and for garnishing. Most gardens have room for one plant of each. If this is your first herb bed, our beginner's guide to growing herbs from seed is the place to start.

Parsley earns its space by being useful on the days when nothing else is ready: it is still standing in February, it takes almost no room, and one properly spaced plant will outlast a whole shelf of supermarket pots. Grow it alongside the chives, dill and basil that share the same bed, keep a few leaves back to freeze for winter — parsley loses most of its flavour when dried but freezes beautifully — and read herb gardening made easy if you are planning a whole herb bed. Browse the full culinary herb and organic herb ranges, everything else in herb seeds, or work through the rest of our growing guides.