Onion ‘Corrado’ Heat Prepared (Spring Planting)

Where to Plant

Plant Onion ‘Corrado’ in an open, sunny position with fertile, moisture-retentive but well-drained soil. Before planting, remove weeds and work in well-rotted garden compost if needed. Avoid freshly manured ground and soil that stays wet, as onions can rot in waterlogged conditions.

When to Plant

Plant ‘Corrado’ sets from March to April, once the soil is workable. If the ground is frozen, waterlogged or particularly cold and wet, wait for conditions to improve before planting.

Planting

Plant each set with the pointed end facing upwards and the tip just showing above the soil surface. Space sets around 10cm apart, with 25–30cm between rows. Gently firm the soil around them and water after planting.

Why Heat-Prepared Sets?

‘Corrado’ sets are heat prepared for 20 weeks to reduce the risk of bolting. Bolting is when an onion produces a flower stem prematurely instead of putting its energy into developing a good-sized onion. Heat-prepared sets are particularly useful if you've experienced onions bolting in the past or grow in an area where spring temperatures can fluctuate. Temperature changes and other growing stresses can still occasionally trigger flowering, so remove any flower stems that appear and use those onions first after harvesting.

Growing in Containers

‘Corrado’ can also be grown in a large, well-drained container. Give the sets enough room to develop full-sized onions and keep the compost evenly moist during dry weather. Container-grown onions will usually need more regular watering than those growing in the ground.

Watering & Feeding

Once established, onions generally only need additional watering during prolonged dry spells. Keep them well watered in dry weather while the bulbs are actively developing and swelling, as a lack of moisture at this stage can limit their final size. As the crop reaches maturity and the foliage begins to yellow and fall over naturally, stop watering to allow the bulbs to mature ready for lifting.

Well-prepared soil should provide a good start. On poorer soils, give plants a balanced vegetable feed as growth gets underway. Avoid excessive high-nitrogen feeding, which can encourage leafy growth at the expense of good bulb development.

Keep Them Weed Free

Onions have relatively shallow roots, so weeds can quickly compete with them for water and nutrients. Weed regularly, taking care not to damage the developing bulbs or shallow roots with a hoe.

Protecting Newly Planted Sets

Birds can sometimes pull newly planted onion sets from the soil before they've rooted properly. Check them regularly and gently push any disturbed sets back into place. Fleece or suitable netting can be used temporarily until the sets are securely rooted.

Good Companions

Grow onions alongside crops such as carrots, beetroot, lettuce and other leafy salads. Their upright growth means they fit neatly into a mixed vegetable plot without taking up too much space.

Making the Most of Your Bed

Quick-growing crops such as radishes and salad leaves can be grown nearby and harvested while your onions are still developing. Just make sure the onions aren't crowded and continue to receive plenty of light.

Crop Rotation

Avoid growing onions where onions, garlic, leeks or shallots have recently been grown. These crops belong to the same plant family and can be affected by some of the same soil-borne pests and diseases.

Planning Ahead

Where possible, leave three to four years before growing onion-family crops in the same spot again. Once your onions have been lifted, the cleared ground can be used for later-sown salads and other quick-growing vegetables.

When to Harvest

‘Corrado’ can begin reaching maturity from around mid-July, with harvesting continuing through summer depending on planting time and growing conditions. Watch the plants rather than relying on the calendar alone. The bulbs are ready to lift once the foliage begins to yellow and naturally fall over.

How to Harvest

Choose a dry day and carefully loosen the soil beneath the onions with a garden fork. Lift them gently to avoid bruising or damaging the bulbs, especially those you plan to store.

Drying Your Onions

Leave freshly lifted onions somewhere dry and airy until the foliage, necks and outer skins are thoroughly dry. In fine weather they can be dried outside; if conditions are damp, move them somewhere covered with plenty of ventilation.

Storing Your Onions

‘Corrado’ is a good choice if you want onions to keep after harvest. Once the bulbs are thoroughly dried, store sound, undamaged onions somewhere cool, dry and well ventilated. Net bags or slatted trays are ideal as they allow air to circulate around the bulbs. Check them occasionally and use any that begin to soften first.

Top Tip

Set aside your firmest, best-ripened onions for storing and use any damaged, thick-necked or bolted bulbs first. Taking the time to dry the crop thoroughly will help your stored onions last longer.

Flavour

‘Corrado’ has a good, full onion flavour with firm flesh, making it a versatile yellow onion to have in the kitchen.

Best Enjoyed

It's an excellent everyday cooking onion. Chop it into soups, sauces, curries, casseroles and stews, or cut the bulbs into wedges for roasting. Freshly harvested onions can also be finely sliced into sandwiches, burgers and salads.

Make the Most of Your Crop

Enjoy some bulbs fresh from the garden during summer and dry the remainder thoroughly for later. Having well-cured onions in store means you'll have your own homegrown supply ready whenever a recipe calls for one.

Top Tip

Smaller bulbs are handy for roasting whole or halved, while larger onions are ideal when you need plenty of slices or chopped onion for soups, sauces and batch cooking.

What to Expect When They Arrive
Your onions are supplied as dormant sets in a netted bag, ready for planting. Sets are sold by weight, so the number of individual bulbs you receive may vary slightly from the approximate count shown on our website.

Ready to Plant
Your onion sets can be planted out as soon as they arrive. Each small bulb will establish roots and grow on to produce a mature onion ready for harvesting.

If You Can't Plant Straight Away
Remove the sets from their delivery packaging and keep them in their netted bag somewhere cool, dry and well ventilated until you're ready to plant. Check them occasionally and plant as soon as conditions allow.