Ready, set, sow – outdoors!

Opportunity expands in the garden this month, with sowing now being made directly into the soil – here’s what you need to know

Making outdoor sowings of fruit and veg in spring is one of the most satisfying moments in the gardening year. As the soil begins to warm and days lengthen, it’s time to turn plans into action. Success hinges on timing, soil preparation and protecting young seedlings from our famously changeable weather.

Start with the soil
Good sowing begins below ground. After a wet winter, UK soils can be cold, compacted and waterlogged. Avoid the temptation to work the soil when it’s too wet; walking on or digging sticky soil can damage its structure. Instead, wait until it crumbles easily in your hand.

Remove weeds thoroughly, especially perennial roots, and rake the surface to create a fine, level tilth for smaller seeds such as carrots or lettuce. For larger seeds like peas and beans, the soil doesn’t need to be quite so fine, but it should still be free-draining and stone-free.

Incorporating organic matter is strongly encouraged. Well-rotted compost or manure improves soil structure, boosts fertility and supports soil life.

Mind the timing
Spring in the UK can be unpredictable. While March may bring warm sunshine, frosts are still common in many regions well into April and even May in the north and in frost pockets.

Always check the seed packet for sowing guidance and pay attention to soil temperature. Hardy crops such as broad beans, spinach and onions can usually be sown outdoors earlier, while tender crops like courgettes and sweetcorn are better started indoors and transplanted after the last frost.

If you’re keen to sow early, consider warming the soil with cloches or horticultural fleece a couple of weeks beforehand. This simple step can make a noticeable difference in germination rates.

Plan your space
Before sowing, think about spacing and crop rotation. Avoid growing the same family of vegetables in the same place year after year, as this can lead to pest and disease build-up and nutrient imbalances. Rotating crops – such as brassicas, legumes and root vegetables – helps maintain soil health.

Mark out drills with string to keep rows straight. This makes weeding and hoeing much easier later on. For small gardens or raised beds, you might prefer block sowing rather than long rows, particularly for salads and herbs.

Sow at the right depth
A common mistake is sowing too deeply. As a general rule, seeds should be sown at a depth around two to three times their own size. Very fine seeds can be sprinkled thinly on the surface and lightly covered with sieved compost or vermiculite.

After sowing, gently firm the soil with the back of a rake or your hand to ensure good contact between seed and soil. Water carefully using a watering can fitted with a fine rose to avoid washing seeds away.

Label everything clearly. It’s surprisingly easy to forget what you’ve sown, especially when seedlings all look similar at first.

Protect young seedlings
Spring can bring heavy rain, strong winds and sudden cold snaps. Once seedlings emerge, they are vulnerable.

Use horticultural fleece to shield crops from frost and to protect against pests such as pigeons and carrot root fly. Cloches and cold frames can provide extra warmth for early sowings. Remove covers during mild days to allow air circulation and prevent overheating.

Slugs and snails are particularly active in damp spring conditions. Check regularly and use environmentally friendly control methods, such as hand-picking at dusk, encouraging natural predators, or using approved organic pellets if necessary.

When seedlings appear, resist the urge to leave them crowded. Thinning is essential for many crops, including carrots, beetroot and lettuce. Remove excess seedlings carefully to give the remaining plants space to grow strong and healthy.

Keep on top of weeds while they are small. Hoeing on a dry day is especially effective, as weeds will shrivel and die on the soil surface. Regular light hoeing is far easier than tackling a jungle later in the season.

Water wise
Spring weather can swing between very wet and surprisingly dry. Seeds need consistent moisture to germinate, so don’t let the soil dry out during this critical period. However, avoid overwatering, which can cause rotting or encourage fungal diseases.

Aim to water in the morning so foliage dries during the day. Once plants are established, water less frequently but more deeply to encourage strong root systems.

Consider successional sowing
To avoid gluts and gaps, sow little and often. Fast-growing crops such as radishes, salad leaves and spinach can be sown every two to three weeks through spring. This approach ensures a steady harvest rather than everything maturing at once.

Similarly, stagger sowings of peas and beetroot to extend your picking season. Keeping a simple garden notebook can help you track sowing dates and refine your timing year by year.

Don’t forget fruit!
Spring is also a good time to sow hardy fruit seeds such as alpine strawberries outdoors. Established fruit bushes and trees will benefit from mulching with compost or well-rotted manure to conserve moisture and suppress weeds.