Basil Growing Calendar: Sowing, Pinching, Picking and Clearing

The year at a glance

Basil is tender, so in most temperate gardens it is grown as an annual. The work is concentrated in two places: sowing in spring, and the overlapping pinching and picking through summer. From mid autumn you are clearing up and storing seed.

Spring is about waiting for warmth

Outdoor soil does not reach 68F (20C) until around the last frost date in most gardens. Anything earlier has to be indoors or under cover. Seed sown outdoors too early does not germinate, rots in the soil, and you sow again.

1. Eight weeks before last frost Decide the variety and how many plants. Keep the number to what you can keep pinching rather than growing more than you can manage.
2. Six weeks before Start sowing in pots on a windowsill. If the room drops below 59F (15C) at night, a lidded box helps the seedlings come up evenly.
3. Two weeks before Once seedlings have two to four true leaves, stand them outside during the day to harden them off. Planted straight out they check and stop.
4. At last frost Plant out once frost has passed, 10 to 12 inches apart, watering the planting hole before you set the plant.
5. Three weeks after First pinch at six to eight true leaves. Skip this and the plant runs up and flowers in midsummer.

If nights below 50F (10C) are forecast after planting, cover with row cover. Cold makes black spots on the leaves.

Early summer is when you build the plant

Growth accelerates sharply as it warms. How many shoots you build in these weeks decides the whole summer harvest. Flower buds also start appearing, so the same round covers pinching and spike removal.

1. Direct sowing Once the soil is warm this is the best time to direct sow. Plants sown now come into production in late summer and carry the second half of the season.
2. Second pinch Take the second pinch to bring the plant to four shoots. Take a few crowded leaves out of the base at the same time to keep air moving.
3. First flower spikes Look down over the plant weekly and cut any shoot whose tip leaves have shrunk, two joints below the spike.
4. Feed and increase watering Feed, and move from one watering a day to two if needed. Running short of water here is what toughens the leaves.

The first few days of settled hot weather bring a sudden jump in light levels. Pots can scorch, so move them into full sun over several days.

High summer: peak picking and peak drought risk

Leaves come fastest now, and a pot can go dry within a day. Repeated evening wilting pushes the plant into flower and toughens the leaves. You will pick more than you can use, so turn the surplus into pesto for the freezer.

A run of very hot days makes the leaves smaller. That is the plant telling you it is tired: pick less and let it recover.

Autumn: take everything before the frost

Growth slows as it cools and stops by mid autumn. Cut back in early autumn to bring out one last flush, and use everything through mid autumn. A frost turns the plant black overnight, so that is your deadline.

1. Early autumn Cut back by about half and feed. In two weeks you get soft new leaves and a second peak.
2. Mid autumn When the seed spikes on your seed plants have dried brown, cut the shoots and dry them indoors. Taken green, much of the seed will not germinate.
3. Once nights drop below 59F Leaf quality falls off below about 59F (15C). Work through the biggest plants, cutting whole shoots and turning them into pesto.
4. Before the first frost When frost is forecast, cut everything. Leaving the plant gains you nothing, because it will not recover.

The signal is not a date. It is nights below 59F (15C) and the first frost forecast.

Winter: seed and soil

Plants outdoors are killed by frost. In most temperate gardens basil cannot overwinter, so clear it and prepare for spring. Overwintering on a windowsill is possible but rarely worth it: light is short, the plant stretches, and it yields less in spring than a freshly sown one.

Growing basil in the same place every year reduces the crop. Replace the compost in containers, and in the ground leave two or three years between plantings.

Catching up if you miss something

Basil finishes within the year, so a missed job cannot be made up next season. Whether there is a way to catch up within the same year makes a large difference to what you pick.

Every one of these remedies depends on getting new shoots. Once the weather has properly cooled the buds will not move, so early autumn is the cut-off.