Vegetable and Fruit Seeds to Sow in May – 2023 Planting Guide

May is a wonderful time to sow vegetable or fruit seeds because the weather is warmer and frost is less of an issue. For gardeners who like being under the sun, the good news is that there is plenty that can be sown directly outside, though there is a lot we can sow indoors, too.If you’re a gardener, you know that May is the perfect time to plant your vegetables and fruits. The weather is still nice and cool for them to grow, but it’s not too hot yet.This month offers some great choices so take a look below at what will work best in your garden!

Sowing Indoors or in Greenhouses

By starting the seeds indoors or in a greenhouse in May, gardeners can effectively lengthen the time available for plants to mature and produce a bountiful harvest. This is particularly helpful for those who wish to cultivate warm-season fruits and vegetables, such as tomatoes, peppers, and cucumbers, which often require a longer growing period to reach their full potential.

Sweetcorn

Sweetcorn is a variety of maize with high sugar content. Originally grown by Native Americans, it is now eaten around the world. It is considered a fruit, a vegetable and even a whole grain.Sweetcorn can be sown outdoors, but in places with inconsistent sunshine, indoors is best. Sow the seeds in modules or deep pots at temperatures of around 18-21 degrees Celsius. Sweetcorn is a heavy feeder, so remember to use plenty of fertilizer as the seeds grow. You can decide when to harvest by testing when the tassels have turned brown. Simply peel back a tiny bit of the husk and make a small hole in a kernel. If watery liquid seeps out, this is a good sign that it the sweetcorn is unripe, while a pasty substance indicates over-ripeness. If cream comes out of the hole you have pierced in the kernel, then you know it is ready.Mice love sweetcorn, so be on the lookout for signs of this pest.

Courgette, Marrow, Squash and Pumpkin

These vegetables are closely related, and they can all be grown in the same way, primarily under some type of cover.These seeds can be placed into pots, in deep compost, with the blunt end of the seed pointing down. Push the seeds under the soil and water frequently. For optimum results, temperatures of 24 degrees Celsius help the seeds germinate. As the seeds get bigger, the temperature can be brought down to 18-21 degrees.Mice can be another pest with these seeds, especially when the seeds are just sown. Grey mould is another problem. Fortunately, it is easily solved by reducing humidity with ventilation and overcrowding of the seeds, especially if the seeds are being grown in a greenhouse.

Tomatoes

Tomatoes add flavour and colour to any summer salad, and they are easily grown in a greenhouse.If you only want to grow a handful of seeds, place two seeds into a 7.5 cm pot, covering with good quality compost. Keep the soil moist but bear in mind that too much water can cause issues with mould. In a week or two, at temperatures of 21 degrees Celsius, the seeds should germinate. After germination, remove the smaller plant. Tomato plants can grow up to 10 ft in height, and their weak stems can be attached to a support.In May, cold wind or draughts, though not as likely, can kill tomato seeds.

Lettuce

Lettuce is leafy, green vegetable and it is known around the world for being an extremely healthy option in salads and other dishes.Baby or little varieties of lettuce are good options for growing indoors, and they will reach maturity in a month or a month-and-a-half. To stretch out the sowing season, you can sow seeds every couple of weeks. They need light to germinate, so they should only be covered with a small amount of soil in the pot. Spray with water so they become nice and wet, then mist every morning so they do not dry out and become spindly. Maintain temperatures at 21 degrees Celsius and be sure to keep the pots facing the sun for at least half of the day. In the absence of a sunny window, use a grow light. Fertilise lightly, and when the seeds are bigger, thin the seeds and place them in individual pots.

Melon

Melons are delicious fleshy fruits. Principally produced in China, Turkey and Iran, they are popular around the world.Sow seeds 1.5 cm deep on a sunny windowsill or in a propagator at 18-21 degrees Celsius. For better results, since melons love copious amounts of sunlight, perhaps a greenhouse is the best place to grow them. Be sure to use well-drained, moist, fertile soil. When the seeds have grown to the size of a walnut, feed with a fertilizer with a high potassium content every week or so. Stop feeding and reduce watering once the fruit starts to become ripe.

Sowing Outdoors

The arrival of spring heralds warmer temperatures and longer daylight hours, which are vital for the growth and development of many plants, lets look at some of our favourite varieties to plant right now.

Carrots

Carrots are great for complementing a range of sweet or savoury dishes.Seeds should be placed in a very sunny spot, where the soil is fertile and well-drained. Clear the soil of any debris so the carrots can grow properly. Sow them 1.5 inches deep in rows that are 15-30 cm apart. They generally do not need a lot of water, but if there is a period of unusually warm weather, watering will be beneficial.To keep carrot flies at bay, cover the seeds with fleece or place barriers. Aphids can cause mould, but aphid colonies can be crushed by your finger.

Beetroot

For novices, growing beetroots is a great way to start because they require little maintenance and germinate quite easily. There are a few varieties, but you could plant ‘Boltardy’ or ‘Touchstone Gold’.Sow three seeds 2.5 cm deep, 10 cm apart and in rows that are 30 cm apart. By May, you will not need any protection for the seeds, but placing them in fertile, well-drained soil is recommended. If the beetroot is not growing as much as you like, then feel free to add some high nitrogen fertilizer. Water every 10-14 days.

Cucumber

Cucumbers grown in your own garden will have a mouth-watering flavour. Originally from South Asia, it is now commonly found across the globe.Cucumber seeds can be sown in fertile soil that attracts a lot of sunlight. It is a good idea to consider covering them with fleece or cloches. Water the soil around the plant but try to avoid wetting the cucumbers directly. Side-shoots can be left on the ground or supported by strong netting.Whitefly, cucumber mosaic virus, and powdery mildew are common pests. Control mildew by keeping the soil moist, stop the virus by destroying infected plants and whitefly can be staved off with sticky traps.

Broccoli

Broccoli, like beetroot, is easy to grow and it is rich in essential nutrients.The vegetable should be sown 2 cm deep – you can use 3 in each hole – with a distance of 30 cm maintained between plants and in rows that are 45 cm apart. This spacing will encourage the development of side shoots. Use liquid fertilizer on a weekly basis.By May, the risk of cabbage root fly will be less, but snails and slugs can still pose a risk.

Swiss Chards

Like other leafy green vegetables, swiss chard is highly nutritious. It is also an alternative to spinach.In well-prepared soil, in a sunny spot, make a shallow drill and sow the seeds around 1.5 cm deep. Cover with soil and water well. Sow in rows that are spaced 40 cm apart.

Peas

Peas are pod fruits, and each pod contains between three and eight peas.Plant pea pods directly into the ground. As they grow, remember to support them with sticks, mesh or wire netting as they grow into plants. Typically, the peas should be planted between 1 and 3 cm into the soil, spaced apart. They will be ready to harvest in three months.

Strawberry

This bright red fruit is juicy, delicious and perfect for summer eating.Strawberries grow easily in well-drained, fertile soil. Avoid planting in places that previously housed potato or tomato seeds, as this can attract vine weevils, which can be controlled biologically. They need sun and shelter. Windy spots prevent pollinating insects from reaching the flowers. Watering frequently is a must, as is avoiding sowing the seeds too deeply or too shallowly. Space planting holes 35 cm apart and rows 75 cm apart.Fleece covering can protect strawberries from overnight frost, while netting can keep birds away. Squirrels, should they be a problem, can be kept out with wire meshing.

Cabbage

Cabbages are common vegetables in our gardens and are packed with nutrients.Cabbages need sunny spots and good soil to thrive, and you should avoid growing them in the same soil you grew them in the previous year. If possible, prepare the soil in autumn by adding manure or compost and letting it set in over the course of winter. Typically, because they take up a lot of space, cabbages are grown in seedbeds and then transplanted to their final growing place. This enables other plants, which take less time to harvest, to be grown in the meantime. They should be grown 30 cm apart. In the initial phases, little water is required, but as the heads start to develop, more water will increase their size.Using insect-proof mesh will help ward off caterpillars and cabbage root fly. Slugs and snails can be controlled with beer traps or biocontrols.

Growing Tips

In general, when it comes to fruit and vegetables, thin out seeds and remove wayward shoots and yellowing leaves. Remember to support peas or any other plants with stalks, keep informed about harvesting times, beware of frost, and keep weeds under control.The days are getting longer and summer is just around the corner. It is a beautiful time of year, so enjoy growing some delicious fruit and vegetables.

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