Month-by-month checklist

APRIL

Sow cordon tomatoes destined for life outdoors this month – start them off in a heated propagator or on a warm windowsill.

After pricking out, begin feeding potted seedlings in the greenhouse with a dilute liquid tomato fertiliser. Water young plants that are under cover with tepid – not chilled – water.

JULY

Glasshouse toms will now start yielding regularly – keep up watering and feeding with high-potash feed. Outdoor cordon plants will benefit from regular sideshooting and training. The earliest outdoor tomatoes may start to ripen.

MAY

Harden off plants for outdoors this month, ready for planting out in June.

Space out potted seedlings as they grow to avoid leggy growth, keeping plants watered and fed as the root systems fill out.

Pot up or move into final containers as the roots fill their pots. Remove sideshoots of cordon varieties.

AUGUST

Yields really ramp up this month, so harvest regularly (start removing any leaves that are shading fruits).

Providing ample water is essential due to mature root systems and summer temperatures, so be vigilant to maximise yields and ensure healthy plants.

JUNE

Water growing bags, soil or containers in readiness for planting.

As soon as the risk of frost has passed, plant outside.

Water the base of greenhouse crops regularly to aid fruit set (very early greenhouse crops may start ripening this month).

SEPTEMBER

Again, yields (especially of cordons) will be impressive this month, so enjoy the bounty. Keep watering and feeding regularly. As temperatures fall with the onset of autumn, ripening will slow.

Move potted plants into greenhouses to ripen up or remove green tomatoes to ripen indoors if you don’t have a greenhouse.