Tips on growing SA’s most popular summer vegetables

mage by Charlotte Baines from Pixabaymage by Charlotte Baines from PixabayGrowing your own vegetables is really worthwhile and although a lot of work, also a lot of fun and a great learning experience. Below you will find some helpful strategies and tips to get the most out of your summer vegetable garden, and how to keep your plants healthy and producing.

Summer is the height of the growing season when the vegetable garden comes into its own, and while some vegetables like spinach, broccoli and cauliflower prefer to grow in the cooler months, others such as tomatoes, cucumbers, and peppers need hotter weather in order to thrive. If you want to get the most out of summer’s bounty you really need to get going now before it’s too late to grow long-maturing summer crops like peppers and tomatoes.

Most vegetables need as much sun as possible, and in order to grow healthy and nutrient-dense crops, it is vital to prepare the beds thoroughly before planting. If you have been practicing organic gardening for a while, your soil should be perfect and you may prefer to use what is called the “no till” method of gardening. If you are just starting out, dig the beds over well, incorporating plenty of well-matured organic materials like compost, or kraal manure. If you want root crops like carrots to grow nice and straight, it is very important to remove all stones from the beds. Lastly, add a generous dressing of a balanced organic fertiliser, as this will get the seedlings growing strongly.

Look out for worm pellets, or earthworm castings, called “vermicomposting”, or a liquid microbial fertiliser tea, called “earthworm tea”. This odourless natural fertiliser is also used as an inoculant for soils, and will suppress airborne pathogenic fungi. The organisms in Worm Tea also produce hormones, vitamins, nutrients, enzymes, amino acids and minerals needed by seedlings, cuttings, and young plants.

Image by Andreas Gollner from PixabayImage by Andreas Gollner from PixabayIf worm tea is applied along with insoluble granulated or powdered minerals such as granite, limestone, rock phosphate, etc., together they will supply 95% of everything the soil needs. The other 5% is organic material like compost which is applied as mulch on the surface of the soil, or is formed from dead root material under the soil surface. The microbes in Worm Tea feed other organisms in the soil food chain, and can be used to fertilise both indoor and outdoor plants, by spraying onto the plants directly, or by applying it as a soil drench.

Working on improving your soil will greatly increase your success rate, and your soil will become so healthy and alive with good organisms, that you will no longer have to continually dig it over – wonderful!

Once the beds are prepared, rake them smooth and level, and water well. If you are using chemical fertilisers, allow the beds to lie for at least a couple of days before sowing seeds, as certain big seeds like beans can be damaged by direct contact with fertilisers.

Grow regionally - pick vegetable varieties that will do well in your particular area. If you live in a region which experiences early frosts and you want to grow slow maturing crops like peppers and tomatoes later in the season, check the maturity date before sowing, as it may be better to invest in well-established seedlings instead. In hot and humid regions many summer vegetables are grown only during the cooler months of the year, and only tropical veggies are grown in the height of summer, so always seed advice from the professionals at your garden centre for the best sowing times for your region.

Grow seasonally - Image by jf gabnor from PixabayGrow seasonally - Image by jf gabnor from PixabayGrow seasonally – select vegetables which are known to do well in summer, and in winter grow those which prefer cooler weather. This is the best way to approach vegetable gardening at home, but can become a bit confusing if you are new to gardening because some vegetables like broccoli, which prefers cooler weather, has been bred to tolerate more heat and can be sown out of season, but my reasoning is, why try to grow vegetables out of season when they are more likely to struggle, when there are plenty of summer veggies to choose from. Planting seasonally also allows for natural seasonal crop rotation to be practiced in smaller gardens.

Remember to plant larger growing varieties of vegetables on the south side of your vegetable garden where they will still benefit from plenty of sunshine, but where they will not overshadow smaller growing crops. To save space in smaller veggie patches it is best to plant crops in small squares, rather than in long rows. Once your veggies are planted, water and feed them regularly for the best quality crops.

Succession sowing and cropping is essential for the average family garden to ensure a more continuous harvest of crops, rather than a huge quantity all at once. It is simply the technique of sowing crops at regular intervals for a continuous supply through the growing season. Generally quick-maturing crops are sown every two weeks, or when the first sowing appears above the ground, you can make the next sowing, and slow-maturing crops are sown at longer intervals of up to a couple of weeks apart.

Intercropping matches a quick-maturing crop with a slower maturing crop. To achieve this, at sowing time, place a quick-maturing crop like radish next to a slower-maturing crop. While you wait for the “long stayers” to come to harvest, quick-maturing crops will be in and out of the garden and onto the table in no time.

Growing vegetables correctly, and at the right time of the year, goes a very long way to keeping them healthy, and some veggies are more disease and pest resistant than others. Good cultural practices such as proper crop rotation, together with good sanitation will go a long way to keeping crops healthy, so keep the beds weed-free, as weeds harbour many pests and diseases, and remove and destroy any diseased plant material.

Nevertheless, your vegetables will need spraying at some time or another, so I highly suggest that you purchase a couple of organic sprays when you purchase your vegetable seedlings or seeds. There is nothing worse than doing all the hard work of sowing and growing them, only to notice one day that they are being affected by something and you have nothing at hand to spray with.

Image by Maya A. P from PixabayImage by Maya A. P from PixabayYou can ask your garden centre for advice on which control measures they recommend for your particular selection of plants, but I do recommend Biogrow organic sprays.

Biogrow ‘Bioneem’ (Insecticide) is the organic gardener’s first choice for keeping nasty pests at bay. This amazingly versatile natural insecticide can be used to protect edibles against up to 200 different types of insects. Bioneem is the perfect alternative to conventional chemical-laden pesticides, and can be used to control fruit flies, white flies, weevils, leaf hoppers and mealybugs to name but a few. Based on an herbal extract from the neem tree, Bioneem gives your plants powerful, lasting protection from all sorts of pests and is completely eco-friendly and won’t cause any harm to the soil, air, water or food being grown. This proudly South African product gives you an easy, effective, and 100% earth-friendly way of defending your garden.

Biogrow ‘Pyrol’ (Insecticide) provides broad-spectrum control. It can be used as a dormant and growing season insect spray and kills all stages of insects, including eggs, on contact. It is a proprietary formulation consisting only of naturally occurring plant oils as its active ingredients. It is truly an insecticide from plants for plants. It does not contain piperonyl butoxide as a synergist, and the active ingredients do not persist in the environment. Pyrol will control insect pests such as aphids; beetles (e.g., Colorado potato beetle, Flea beetle, Japanese beetle, asparagus beetle); caterpillars (e.g. gypsy moth caterpillars, tent caterpillar, diamondback moth larvae, leaf rollers); ants; mealy bugs; mites; leafhoppers; scale; whitefly; adelgids; plant bugs; fungus gnats; thrips; sawfly larvae; psyllids; spittlebugs; and phylloxera.

Biogrow ‘Vegol’ (Organic Insecticide) is a contact insecticide with ovicidal activity that can be used in both the dormant and growing seasons. It is a proprietary formulation consisting of pure canola as active ingredient that kills all stages of insects. The active ingredient does not persist in the environment. Vegol will control insect pests such as aphids, mealy bugs, mites, leafhoppers, scale, whitefly, adelgids, immature plant bugs, sawfly larvae, psyllids, leaf beetle larvae and phylloxera. For use indoors, outdoors and in greenhouses, on fruit and nut trees (e.g. apples, cherries, peaches, pears, nuts); flowering, foliage and bedding plants; corn; soybean; melons; tomatoes; vegetables (e.g. beans, cabbage, cucurbits, peas, potatoes); figs; small fruits (e.g. grapes, strawberry, raspberry); citrus; ornamental and shade trees (e.g. birch, evergreens, holly, oak); and houseplants.

Biogrow ‘Copper Soap’ (Fungicide) will control fungal diseases such as: Powdery mildew and downy mildew on vegetables and ornamentals; rust on ornamentals; late blight on potatoes and tomatoes and Peronospora and downy mildew on grapes. This product is a patented, fixed copper fungicide, made by combining a soluble copper fertiliser with a naturally occurring fatty acid. The copper and the fatty acid combine to form a copper salt of the fatty acid, known technically as soap. The copper soap fungicide controls many common diseases using low concentrations of copper, down as low as 90 ppm. The net result is an excellent vegetable, fruit and ornamental fungicide. It decomposes to form soluble copper, and fatty acid, both of which can be used by microbes and plants. The copper soap is suited for use in domestic circumstances, both indoors and outdoors. It controls diseases of a wide range of plants, including many vegetables, fruits and ornamentals. As with most fungicides it acts to protect plants from infection. Therefore, it is important to have the copper soap on the leaf, flower or fruit before the pathogen is able to cause an infection.

I hope you found these tips helpful, and now onto the veggies.

Green BeansGreen BeansGreen Beans

Green beans must be the easiest vegetables to grow, and are sown anytime from late September to October, with successive sowings up until about the end of December or January, depending on your first frost date. In regions with only light frost sowing starts as early as August and continues until January, February or even March. In hot frost free regions sowing only starts from about February and can continue through the winter months to about August or September.

Although beans are a summer crop which can take a lot of heat, they dislike extremely hot dry conditions, so it is essential to water your beans regularly, especially during the flowering and pod setting time. Dry conditions can cause petal drop and affect the crop adversely. Keep the soil moist but not saturated; never allowing it to dry out totally. Beans have shallow roots, so mulch the soil with a thick layer of compost to help keep them cool in hot weather. Hosing the foliage down during hot, dry weather also keeps the plant refreshed, and discourages infestations of pests like red spider.

Most dwarf bean cultivars will reach picking maturity within 50 to 60 days, and runner beans usually take 10 to 14 days longer to reach maturity. The dwarf varieties start bearing sooner than the runners but the runners continue bearing for longer. For successive plantings sow dwarf beans every 3 to 4 weeks, and runner beans every 6 to 8 weeks.

Members can click here to read more about growing green beans


Beetroot is an intermediate to warm season crop but can be grown almost throughout the year in South Africa, with spring to autumn being the best time to sow in frosty regions. Beetroot is semi-hardy to frost but in cold regions winter sowings will grow slowly with poorer yields. In hot, sub-tropical regions beetroot is only sow in autumn and winter.

Beetroot loves sun and requires good soil preparation, as for all root crops, with all hard clumps of soil broken down and stones removed. It needs to grow quickly and be ready to harvest within 8 to 10 weeks after sowing, depending on the variety. To speed up germination, soak the seed overnight in water before sowing, and because seedlings do not always transplant well, it’s best to sow the seed directly into your beds, in shallow furrows about 3cm deep, and to space the plants correctly, depending on the variety being used. Do not bank up the soil against the roots of beetroot.

Each beetroot seed is actually a cluster of up to 5 seeds, so it is essential that you thin out the crop when the seedlings are about 5cm high, by gently tugging out the extra seedling in the clump.  Always keep the soil moist but not saturated, because a sudden lack of water can spoil the quality of the crop.

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Carrot 'Rainbow Mix'Carrot 'Rainbow Mix'Carrots

There are several varieties of carrots to choose from for the home garden, including small finger carrots which can easily be grown in pots. Although carrots are known as a crop which does best under cooler growing conditions, modern hybrids are available which allow carrots to be grown virtually throughout the year. If the correct varieties are selected for the season, the best sowing times in are as follows:  In cold areas which experience heavy frost carrots are best sown from August to March. In warmer areas which experience only light frost they can be sown almost year-round, from January to November, and in hot, subtropical regions they are only sown from February to September.

It is not recommended that fresh manure or compost be added to the beds as this may cause unattractive, hairy roots, with a coarser texture. If you plant carrots in beds that previously held leafy vegetables like cabbages, which are heavy feeders. The soil should be rich enough for growing carrots, and it may not be necessary to give any additional feeding at all. Carrots need plenty of sunshine and a lot of phosphorous to develop strong, good quality roots, and on lighter textured soils, where leaching is more prevalent, about half the potash is often supplied in side-dressings of fertilisers during the growth period. For the home gardener any balanced organic fertiliser which is high in phosphates, like 2:3:2 can be applied, usually at 4 weeks, and again at 8 weeks after planting.  An organic slow release fertiliser like: Biogrow ‘Biotrissol’, and bone meal, are also good organic sources of phosphorous

Carrots do not transplant well so sow the seed directly into furrows about 1cm deep. The seeds are sometimes slow to germinate, and they may even take several weeks to show any signs of life. Depending on the variety, crops should be ready to harvest between 8 to 16 weeks, generally, successive plantingsare sown every 3 to 4 weeks, depending on the variety.

Carrots require deep watering, ensure that the soil is wet to a depth of about 30cm, as frequent shallow watering will not produce good results. To avoid green shoulders to the roots, bank the soil over the roots lightly as they develop.

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Cucumber 'Patio Snacker'Cucumber 'Patio Snacker'Cucumbers

Cucumbers are fast growing, warm season crops, and in the warmer regions of the country seed can be sown from spring to mid-summer, and in cold regions from late spring to early summer. In humid subtropical regions they are planted out during the coolest months.

In home gardens they must be y are best trained up a trellis of some kind, at least 2m high. Tie the stems up as they grow and encourage them to bush by pinching out the growing tips when the plants have 6 true leaves. Once they reach the top of the trellis, pinch out the growing tips again, and continually pinch back very long side shoots to encourage more fruiting.

Cucumbers love good air circulation around their leaves, and require well-prepared beds.  Water your plants regularly, as a lack of moisture can lead to poor flower production and wilting of the leaves. When your cucumbers start to flower feed every 4 weeks with a balanced organic fertiliser that is high in potassium, keeping it well away from the stems, and watering it in well. Feed again after 3 to 4 weeks, and mulch the plants with compost, but also don’t let it touch the stems. Depending on the variety grown, cucumbers will be ready to harvest in about 8 to 10 weeks.

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Egg Fruit 'Pinstripe'Egg Fruit 'Pinstripe'Egg Plant

Eggplants are warm season crops and in the subtropical regions of the country they can be sown from very early spring right through to late summer and autumn. In cold and frosty regions they are only sown once all danger of frost is over, and if you live in a region which experiences early frosts, it is best to plant out established seedlings later in the season, so check you maturity dates before sowing seeds.

For best results, eggplants require full sun, and must grow quickly, so prepare your beds thoroughly. Good air circulation is essential to prevent fungal diseases, so space your plants correctly for the variety you are growing. During hot and dry weather, mulch around their roots to help keep moisture in the soil, and be sure to water regularly or the fruits will be small and bitter. Once the plants start flowering feed them every 4 weeks with a balanced organic fertiliser that is high in potassium. Eggplants should start bearing fruit after about 14 weeks in the ground and will continue to produce fruit for many months, until the onset of cold weather.

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Leeks are a good intermediate to cool season crop which have a better flavour when harvested in the cooler months. They are not as fussy about day length as onions, and leek cultivars fall into two distinct categories. The so-called ‘”summer or autumn leeks” which are sown in spring and early summer for harvesting in late summer, autumn, and even early winter; and the hardier overwintering, or “frost-tolerant leeks” which can even be harvested in the middle of winter. Varieties intolerant of the cooler conditions will bolt to seed prematurely when grow in climates to which they are not suited, so check with your local garden centre as to which varieties are best suited to your region. In subtropical and tropical regions gardeners will tend to find it easier to grow a crop of leeks than a crop of onions. In these regions leeks do well if sown in from March until July, and crops can be progressively harvested before the onset of hot summer weather.

Leek seedlings must be about 10cm tall and have stems as thick as a pencil before you transplant them. Plant them into trenches about 20cm deep and space your seedlings about 15cm apart. Place the seedlings into the trenches and just cover the roots with a little soil. As they grow, slowly fill up the trenches with soil. This is called “blanching” and gives you that lovely white stem as well as improving the flavour and texture.

Water deeply on a weekly basis if the weather is dry, and regular feeding gives the best results, so feed every two weeks with a balanced liquid fertiliser that is high in nitrogen.  Leeks are slow growing; and although you can start harvesting after about 11 weeks, when the stems are about 1 to 2cm in diameter, they can take 15 to 20 weeks to reach full maturity. For successive crops plant out seedlings every 8 weeks in the growing season.

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Loose-leaf Lettuce Loose-leaf Lettuce Lettuce

Everyone wants lettuce in summer, but unfortunately it is not always easy to grow when temperatures are very high, growing best as an intermediate to cool season crop. There are varieties that can be sown almost all year round, so ensure that you are growing the correct variety for the season and your region, because the plants will go to seed quickly in hot weather if the incorrect variety is grown. In subtropical regions lettuce is only grown during the coolest months.

The loose-leaf lettuces are the easiest to grow in summer, as they are less susceptible to changes in temperature. They are attractive growing in containers, and because they do not form heads they can be harvested continually until they go to seed. A covering of a 30% shade cloth will benefit lettuce greatly in summer.

Seed can be sown into seedling trays or directly into the garden, but take great care when planting out lettuce as they can break easily, and transplant only in the cool of the day. Lettuce grows quickly and must be watered regularly or the leaves will turn bitter, so keep the soil moist at all times without over watering. Mulching the soil around your plants will help to keep the roots moist and cool, and 3 to 4 weeks after planting out feed them with a balanced organic fertiliser that is high in nitrogen, and repeat again after 3 weeks.

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SweetcornSweetcornMaize and Sweetcorn

Maize and sweetcorn are summer crops which are sown from spring to mid-summer. Sweetcorn is more sensitive to low temperatures and should be planted out only when all danger of frost is over. Both grow in any well-drained soil but for best results add compost and a dressing of organic 2:3:2. Always place the fertiliser next to the sowing furrows so that the fertiliser does not come into direct contact with the seeds. The plants are pollinated by wind, so sow in short blocks of 3 to 4 rows about 1 to 2m long.  Sow the seed thinly with about 15cm between the seeds; later you can thin them out to about 30cm apart. Mulch the plants and water regularly and deeply, feeding every 4 weeks with a balanced organic fertiliser that is high in nitrogen. 

In relation to maize, sweetcorn matures much earlier and is generally a shorter plant. Many varieties will send out suckers which are called “tillers”. These will not affect the yield and are often harvested as baby corn. For baby corn leave the first cob to form fully and then harvest subsequent cobs when they are in the milky stage and as soon as they start to silk. The main cobs can be harvested about 9 to 12 weeks after sowing when the silks turn brown and the kernels are full and exude a milky sap.

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Marog 'Red Stripe'Marog 'Red Stripe'Marogo

Marogo is an erect, annual weed, occurring in great abundance in the tropical and subtropical regions of Africa and the Americas, where it is used as a green vegetable, much like spinach. It loves moisture and thrives close to water, and on moist and disturbed land, like ploughed fields, cultivated meadows, fallow farmlands and waste areas, as well as gardens. Although easily controlled and not particularly competitive in the garden, it is recognized as a harmful weed of North American agricultural crops like maize. This annual produces a tap root and erect, but often branched stems, which can reach 1 to 2m in height if the plants are allowed to reach maturity in the garden. The stems are thick and often ribbed or tinged with red; and at maturity, the entire plant may be reddish in colour. For the best flavour sow the seed thickly and eat the tender tops when they are about 25cm tall by cutting them off with a scissors and then leaving them to re-grow.

Marogo must be grown in full sun and will not tolerate shade, and as long as it can be watered freely it thrives under hot summer conditions that would be far too high for Swiss chard. Seed can be sown from spring to late summer, and germination is usually rapid if the soil is warm. Most importantly, the plants require well-drained soil, and thrive on light (sandy), to medium (loamy) soils. If your soil is relatively fertile, a dressing of compost should be sufficient and the plants will need no additional fertilisation.

It is best not to fertilise at all, and if you do, never use inorganic fertilizers, because, although no members of this genus are known to be poisonous, when grown on nitrogen-rich soils, they are known to concentrate nitrates in the leaves. This is especially noticeable on land where chemical fertilisers are used. Nitrates are implicated in stomach cancers, some other health problems, so it is inadvisable not to eat this plant if it is grown inorganically.

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Okra flower and pods - Image by anjuvn from PixabayOkra flower and pods - Image by anjuvn from PixabayOkra

Okra is a tall growing, annual crop that loves full sun, grows quickly to about 2 meters tall, and produces large, attractive, hibiscus-like yellow flowers in summer. Okra is grown throughout the temperate regions of the world and it grows so vigorously in warm subtropical climates that a single plant can produce up to a 100 pods. Pods can be harvested within 50 to 60 days after transplanting, when they are young and tender and about 8cm long. Do not leave them on the plant for too long as they get hard and stringy quickly. Pick the pods regularly, as frequent harvesting encourages the plant to produce more flowers and pods.

Pod production diminishes in cool weather, and in cold winter regions, sow seeds when all danger of frost is over, in rows about 40cm apart. Thin the seedlings out until they are spaced about 30cm apart. Okra grows best in good, well-drained soil but will tolerant poor soils and even heavy clay. It is drought hardy but responds best to regular watering. Feed your plants monthly with a balanced organic fertiliser.

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Chillies Chillies Peppers & Chilli Peppers

Sweet or Bell Peppers are warm season plants which can be grown virtually throughout the year in subtropical regions; however, in humid regions fungal diseases are a problem in summer. In temperate regions seed can be sown in early spring to midsummer, but in very cold regions which experience early frosts, the growing season is short, and it is best to plant immediately once all danger of frost is over, and later in the season, it would be best to plant established seedlings.

Chillies or hot pepper varieties are tropical plants ideally suited to hot and moist tropical and subtropical conditions, where they can develop into perennial bushes with quite a long lifespan. However, they are very adaptable and will even do well in semi-arid regions if watered well. In colder regions frost kills them off, so in these regions they only grow as summer annuals, and because the growing season is short, it is best to plant them out as soon as all danger of frost is over, and later in the season, it would be best to plant established seedlings.

Peppers and chilli peppers love full sun and must grow quickly, so prepare the beds well. Water regularly, and feed occasionally with a fertiliser that is high in nitrogen, but once they start flowering feed every 4 weeks with a balanced organic fertiliser that is high in potassium. They will start bearing about 11 weeks after transplanting, depending on the type grown, and will produce fruit for many months, until the onset of cold weather.

Members can click here to read more about growing chilli peppers

Members can click here to read more about growing peppers

Squash Squash Pumpkins & Squash

Pumpkin and squash are easy to grow warm season crops which are sown in spring to early summer in cold winter regions, and in the hot and humid subtropical regions they are sown from February through to August. All varieties grow quickly in full sun and can be harvested for a long period. The plants are usually large trailing vines that need plenty of space to grow, but new hybrid seeds are available that produce more compact plants and fruits.

Pumpkins and squash require full sun and a rich soil which drains well, so prepare your beds thoroughly. Do not overwater the beds until the seeds germinate, and thereafter water regularly, especially in hot weather. When the plants start flowering, feed them occasionally with an organic fertiliser that is high in potassium, and mulch the beds to conserve moisture and to keep the roots cool.

Small fruits like baby marrow and patty pans must be harvested regularly, when they are still small and succulent. Pumpkins are harvested when they are fully mature and need a long growing season of about 14 to 20 weeks to fully mature, and remember that the larger fruiting varieties will take even longer to mature than smaller hybrids. Large fruits can be harvested for storage over winter when they are fully mature and the plants die down in late summer.

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Radish 'Sparkler'Radish 'Sparkler'Radishes

Radish is extremely easy to grow in full sun, and it’s best to plant sow directly into garden beds or window boxes and other containers, so as not to disturb their roots. Seed can be sown almost throughout the year in South Africa, however, in very hot summer regions, high temperatures may cause radishes to bolt, making them essentially useless. 

Radishes grow quickly, and should be ready to harvest within 3 to 5 weeks, depending on the season, and the variety sown. Select a sunny spot because,  if radishes are planted in too much shade, or even where neighbouring vegetable plants shade them too much, they will put all their energy into producing larger leaves, rather than their edible roots.

All root crops require soil that has been thoroughly dug over, with all hard clumps of soil broken down and stones removed. Germination should take place within 5 to 7 days, and thinning out is done to space them correctly, and will depend on the variety sown, so follow the instructions on your seed packet to get the correct spacing. For successive crops you need to sow seed every 3 to 4 weeks. Because radish matures so quickly, extra feeding won’t be necessary, even if you are growing them in pots.

Always keep the soil consistently moist but not saturated, as a sudden lack of water, or alternatively, too much water, can spoil the quality of the crop by causing the roots to split open. Do not leave radish too long in the soil, as this will cause them to lose their flavour, and they quickly become woody and tough.

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Spring Onions Spring Onions Spring Onions

Spring onion seeds can be sown directly into the soil at any time of the year, except in cold regions where sowing in April and May should be avoided. To prevent misshapen or stunted crops, root vegetables require soil that has been thoroughly dug over, with all hard clumps of soil broken down and stones removed.

Thin the seedlings out to space them 7cm apart, and because spring onions should be grown quickly, feed them lightly every two weeks with a balanced organic fertiliser that is high in nitrogen. Unlike onions, in order to blanch the stems, a hill of soil must be built up around spring onion plants as they mature. The plants can be harvested when the stems are pencil thick, about 90 to 120 days after sowing.

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Sweet PotatoSweet PotatoSweet Potato

The sweet potato is a perennial, tropical vegetable which thrives in heat and humidity, making it ideal for our subtropical regions, where it is planted out in October and November, but plantings can continue up to about March. Because sweet potatoes have a growing season of 3 to 5 months, in cold winter regions plant as soon as the soil is warm enough. This crop requires plenty of sunlight, thriving on fairly deep, sandy loam which drains well. Very poor, sandy soils, and clay are not recommended, as well as very rich soils in which there will be very lush top-growth at the expense of the tubers, which will be long and thin. For this reason fresh compost or manure should not be worked into the soil immediately before planting.

Sweet potatoes are usually propagated by means of rooted shoots or vine cuttings, and a few online suppliers like offer them. Luckily sweet potatoes are easily grown from a few well-shaped, disease-free tubers bought from the store or local farmers market.

It is possible to plant the crop successfully on level soil and then simply allowing it to spread as a groundcover, but better yields are obtained by planting on top of  flattened ridges, about 25cm high. Space the ridges about 90cm to 1m apart, and space the shoots 30cm apart. As the plants grow, draw up soil to the main stem to ensure a good yield and to prevent the sweet potato weevil from reaching the roots through cracks in the soil. On open soil it is advisable to occasionally lift the longer vines to prevent them from rooting at the joints, or they will put all their energy into forming many undersized tubers at each rooted area rather than ripening the main crop at the base of the plant.

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Tomato Heirloom 'Rainbow Blend'Tomato Heirloom 'Rainbow Blend'Tomatoes

Tomatoes are warm season plants which require full sun, and because they are slow-maturing, in cold winter regions seeds are often sown indoors to plant out in spring once the weather warms up, and planting can continue until November or the latest December. In very hot or humid subtropical regions tomatoes are only sown in late summer (February) and planting can continue through autumn to July.

The commonly grown varieties can be divided into two types, determinate (short) and indeterminate (tall) varieties. Determinate tomatoes grow about 1 to 1.2m tall and both the top shoot as well as the side shoots form flowers and fruits. Indeterminate tomatoes will keep on growing until the top growing tip is pinched out as well as the side shoots. Indeterminate tomatoes must be tied up onto stakes about 2.5m high and are usually pruned to have only one or two main stems, and all the side growth is removed.  Miniature and dwarf varieties will grow easily in containers and hanging baskets.

Tomatoes are greedy plants, so prepare the beds well, and add a generous dressing of bone meal or rock phosphate to boost fruit production. Dig large, individual holes for each plant, 45cm square and deep, and unlike other vegetables, tomatoes do best if transplanted several times into pots, before being planted into the garden. Each time you transplant them bury the bare stem deeper, right  up to the first two leaves, and this transplanting can be repeated 2 or 3 times. Finally plant them into the garden when they are about 25cm tall, spacing your plants according to the recommendations for that type.

Because tomatoes are greedy plants, prepare the beds well, and add a generous dressing of bone meal or rock phosphate to boost fruit production. Feed your young plants with a high nitrogen fertiliser for the first 18 weeks of growth, and foliar feeding regularly during the season with a seaweed product will encourage strong growth and help prevent diseases. Midway through the growing season, top dress the plants with several inches of well-aged manure, and once they start flowering and fruiting, feed every 4 weeks with a specialist tomato food, or fertilisers for fruit and flowers.

Members can click here to read more about growing tomatoes