Parsley

Light and exposure

Parsley grows well in full sun as well as partial shade, which makes it an easy herb to fit into the garden. In the middle of summer, a slightly shaded position in the afternoon spares it from suffering the heat and running to seed too quickly.

In a pot on a windowsill or a balcony, give it light without scorching sun all day long. A parsley that receives a few hours of morning sun and brightness the rest of the time produces abundant, tender foliage.

Watering

Parsley likes soil that stays cool. Water regularly so the soil never dries out completely, especially in hot weather, because dry soil pushes the plant to run to seed and toughens its leaves.

In a pot, the substrate dries out quickly: check the soil with your finger and water as soon as the surface is dry. Avoid soaking it, however, as permanently waterlogged soil favours root rot.

Soil and repotting

A rich, loose and deep soil suits it best. Parsley develops a taproot, so it appreciates soil loosened deeply and enriched with mature compost before sowing.

In a pot, choose a fairly deep container, at least twenty centimetres, with good drainage. A quality vegetable potting mix with a little compost added supports a fine production of leaves over several months.

Temperature and humidity

Parsley is hardy. Its rootstock withstands frost down to about minus ten to minus twelve degrees Celsius, enough to get through a temperate-climate winter in open ground without special protection, from USDA zone 5 upwards; the rootstock starts up again as soon as the soil warms. It is a biennial: the plant established in spring gets through the winter, then runs to seed and dies during its second year.

In practice, a spring sowing gives leaves from summer until the frosts, holds on through winter at a slow pace, then still provides a few harvests at the start of the following season before flowering. For tender parsley continuously, it is better to resow each year rather than rely on the old plants.

Pruning and upkeep

Harvest by cutting the outer stems at the base, those that surround the heart of the clump. The plant then continues to produce new leaves from the centre. Cutting too high leaves useless stubs and tires the plant.

When a plant starts to bolt, a tough flower stem rises up at the centre. This bolting signals the end of tender leaves. Cut it off if you want to gain a few harvests, but be aware that a plant that bolts is nearing the end and that you need to prepare the succession with a new sowing.

Pests and diseases

Parsley is fairly robust, but a few troubles recur here. Powdery mildew can cover the foliage with white felting in mild, damp late-summer weather. Rust, with its little orange pustules under the leaves, sometimes appears in the same conditions. Air the plants and avoid wetting the foliage in the evening to keep them at bay.

As for pests, the carrot fly, Psila rosae, attacks the Apiaceae and parsley does not escape it: its larvae bore into the roots. An insect netting placed over the sowing is the best defence. Slugs, for their part, readily devour the young seedlings in spring.

Propagation

Parsley is propagated by sowing, either directly in place or in modules. Sow shallowly, at half a centimetre, in soil kept moist. Germination is slow and capricious, count on two to four weeks. An old trick is to soak the seeds overnight in lukewarm water before sowing to speed up emergence.

Sow several times over the season, from spring to midsummer, to always have young, productive plants. Parsley also self-seeds if you let a plant run to seed: you will find young spontaneous seedlings the following year.

Month-by-month care calendar

Green Hub tips

• Soak the seeds overnight in lukewarm water before sowing: parsley germination is slow, this bath wakes it up.
• Resow each year rather than keeping the old plants. In the second year, parsley runs to seed and the leaves toughen.
• Always harvest the outer stems at the base, never the heart. The clump then starts up again from the centre and produces for a long time.
• A summer sowing well established before autumn gets through the winter outdoors and starts up strongly as soon as the soil warms at the end of winter.