What to harvest, plant and sow in the garden in September

Consider this your early spring gardening guide! Here’s what to harvest, plant and sow in the garden during the month of September


What to harvest in the garden in September

– Early spring is asparagus season. If you’ve just planted your asparagus crowns, cut only a few spears this year (when they’re about 15-20cm long) and gradually increase your harvest in following seasons. Asparagus beds take about 4-5 years before the entire crop can be picked. Let the remaining spears turn into ferns and don’t remove until they’re brown so the energy goes back into the plant.

– After harvesting carrots lose their taste and juiciness very quickly so they’re at their most delicious straight from the garden. Thinning your crops several times through the growing period ensures nice big carrots at the final harvest, and the thin carrots you take out can be used in stir-fries and salads.

– When broad beans are at full height and have produced plenty of flowers, cut the tops off plants. Pick pods regularly to encourage plants to keep producing more. Slice up young pods whole, or leave them a little longer and shell them. As always with veges, the younger you pick them, the sweeter the taste.

– Avocado trees can take 2-4 years before they fruit and it can take up to a year after flower pollination before they ripen. Pick when they reach full size or skin darkens, then keep at room temperature until they soften.

– Leave leeks in the ground until you’re ready to harvest but don’t let them flower. Ideal picking size is about 2.5cm in diameter.

– Pick the outer leaves of non-hearting lettuce such as cos and Little Gem but wait for the head to form on crisp hearting lettuce such as iceberg. Crisp head lettuces last longest in the fridge.

– Harvest early-maturing onions when tops start to go brown, or earlier if you’d like to use them as spring onions.

What to sow in the garden in September

– Sow cabbage seed into punnets or pots to be transplanted into the garden when seedlings have 4-5 leaves.

– Sow parsnip seed directly into the ground and thin out seedlings to roughly 10cm apart when plants produce their third pair of leaves. Fresh seed is best with parsnip as their viability (ability to germinate) can be quite short.

– For young gardeners fast-growing radishes are an ideal crop to sow, either directly into the ground or in pots (the best course of action in very frosty places).

– Sow lettuces a few seeds at a time, successively every 2-3 weeks, at a depth of 6mm or less.

– Also sow seed for beans, courgettes, tomatoes and cucumber in pots under cover, for planting out when weather warms up. All need warm temperatures (18-25°C) for best growth.

What to plant in the garden in September

– If the ground is still very cold in your area avoid planting early potatoes directly into the garden as this will encourage disease. Try them in large containers instead.

– Broad beans are said to help deter pests from attacking potatoes (and vice versa) so try planting some near each other.

– Yams can be sprouted like potatoes by sitting them on a tray or egg carton in a dry place for a few weeks. Plant out in garden after last frost, ideally in a sunny site with light, fertile, well-drained soil. If frost does damage leaves, most root vegetables will usually sprout again once the temperatures rise. Yams can be grown in warmer parts of the country all year round but only in late spring and summer in frosty regions.

– It’s not too late to plant rhubarb crowns or divide existing plants to form new crowns. Add organic matter such as compost and manure to well-drained garden beds before planting.

– Sow super-nutritious broccoli in punnets or trays in a sheltered, light area and plant out seedlings, once they’re about 10-15cm high, into well-drained but moisture-retentive, fertile soil. Protect young seedlings from birds and caterpillars when planting out in a warm, sunny position.

Words by: Carol Bucknell. Photography by: Maree Homer/

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