Asparagus

Posted on by

Conditions

Meticulous ground preparation is essential if asparagus is to thrive. Remember that you are effectively laying the groundwork for two decades of growth, so time spent now will be repaid many times over in the years to come. There is little point rushing this job!

Asparagus prefers a free-draining but nutrient-rich soil that’s not too acidic. Aim for a pH of around 6.5-7.5, adding lime to the soil if yours is below this. Pick a position in full sun, free of frost pockets, where the plants can grow undisturbed and protected from strong winds. Some shade is tolerable but you will get a better performance when plants can draw on good, steady sunlight. Bear in mind that young trees and shrubs nearby may grow larger to eventually cast shade over your asparagus crop. Plants may be grown in any plot that satisfies the above requirements, but heavy clay that hasn’t been improved in the past may prove a challenge. Consider dedicating an entire raised bed to asparagus in these circumstances, when the extra depth of soil will make all the difference.

Prepare the ground the autumn or winter before planting by digging in ample well-rotted manure or garden compost – at least a bucketful per square metre. About a week prior to planting, rake in a general-purpose organic fertilizer, such as bonemeal to give the soil a final boost for your new introductions.

Growing

You can grow asparagus from seed or by planting rootstocks (usually one year old) called ‘crowns’. Growing from seed is cheaper than starting from crowns but you’ll have to wait another year before you can begin harvesting. Considering a bunch of supermarket asparagus costs as much as two ready-to-plant crowns, in most circumstances the latter option is well worth the investment.10 crowns costing about £15 should supply more than enough spears for the average family.

Crowns are generally planted in late March or April into prepared ground, though you can establish them in the autumn, too. Whether growing in raised beds or open ground, begin by digging out a trench 20cm deep and about 30cm wide. If your soil hasn’t been cultivated much in the past, an additional layer of compost or manure may be placed into the bottom of the trench then covered with a similar depth of soil to add more nutrients for the roots to grow into. Now add a line of compost along the bottom of your trench to create a raised mound. This will lift the buds of the crowns above the roots and help excess moisture to drain away from the delicate buds. Make sure that the roots are completely hydrated by soaking them in a bucket of water while you prepare the trench.

Set your crowns into the trench at least 30cm apart, straddling the roots either side of the raised mound, then fill back the soil so that the buds sit just beneath the surface. The trench can be filled in gradually during the growing season as the shoots grow, so that by autumn the level of soil in the trench will match that of the surrounding ground. If you intend to grow more than one trench then set these 45cm apart to give each row plenty of space.

Care

Each spring, just before the crowns launch intro growth, apply a generous handful of organic fertilizer around the base of each plant to give it a boost. A further feed later on in the season may be applied after the cropping period to recharge the exhausted soil. Early shoots will need some protection from late freezes to keep them in good condition – be on hand with fleece if a frost threatens.

The spear cutting period runs from about early April to mid June, after which time the spears should be left to grow on to unfurl into the beautiful fern-like foliage. As this continues to grow you may need to protect it from wind damage. A simple perimeter of canes and string will keep the foliage propped up and safe from snapping. Although the mature foliage may seem of little consequence to the food grower it has a vital role, trapping the sun’s energy and channelling it back down to the crowns for next year’s crop. Protecting this foliage will safeguard future harvests

Harvesting

If you simply can’t wait to make a harvest then a few spears may be taken in the second year following planting. Cut just one or two per crown and stop here. It may seem like a waste to allow the remaining shoots to go uncut, but the first few years are about establishing a healthy root system that will secure the plants for the future. Patience really will be rewarded, so bear with this establishment phase.

Of course, from the third year you can begin cutting in earnest. The first spears nudge through the ground from about early to mid April. Allow a cutting period of eight weeks from this point, taking the last cut in about mid June to let the foliage develop and recharge plants. Spears may be cut once they reach about 10-15cm high – leave them to grow longer and the outer skin becomes tough and will need peeling. To cut, insert a knife next to the spear and cut it off 5cm below ground level so you get some pure white stem with the spear. Any sharp, serrated blade will do the job but special asparagus knives will help as they are purpose-designed for the task, giving a good angle for a clean edge. Cut all the spears – thick and thin – because it is this harvest that stimulates new shoots to appear.

Of course, asparagus is best enjoyed as fresh as possible and will be bursting with flavour and nutrients at the point of harvest. If you want a bigger batch of spears then a previous cut may be kept in the fridge for up to a week while more are gathered. Stand the spears upright in 2cm of cold water before placing the whole container into the fridge. They will also freeze very well after being cut into sections and blanched in boiling water for a couple of minutes beforehand. This gives a great excuse for growing more crowns than might otherwise be enjoyed in the short cropping season – and who could ever tire of this decadent vegetable?!

 

 

Gooseberries

Posted on by

Conditions

Not many fruits are as easy-going as gooseberries, which will grow happily in most soils and can even tolerate partial shade. They prefer cooler conditions, so are great for northern gardens where other sweet crops may struggle. The further north you are, however, the more important it will be to plant your gooseberry in full sun, to make the most of its warmth. Pick a site that’s free of frost pockets, too. The plants may be very hardy – but they flower early in the spring and can suffer at the hands of a late cold snap, which will damage the blossom, reducing the number of fruits that set.

Any well-drained soil will be suitable for a gooseberry. As plants will be in the ground for anything up to a couple of decades, it is worth taking some time to prepare the ground diligently. Incorporate very generous quantities of compost or well-rotted manure to boost the nutrients available. If you have the time, dig this organic matter in a month or two in advance, to enable the soil to settle back down. Alternatively, enrich the growing medium at planting time by digging out generous holes and filling the bottom of them with a layer of compost or manure. Cover this over with another of soil before placing the gooseberry, to prevent root scorch.

Planting:

Gooseberries are available either bare-rooted or container-grown. The former may be planted in the autumn as soon as they become available, or in February or March once the worst of the winter weather is over and soil conditions allow. Container-raised plants can be set into place at any time of the year, barring the middle of summer – spring is an excellent time of year to think about planting one.

The easiest way to grow a gooseberry is as a bush on a short leg (stem) of about 10cm from which all the branches emerge. Bushes need enough room to grow and also to make the fruits easy to pick, so leave 1.5m between them in each direction. Set plants into their holes so that the nursery soil line is level with the ground, and firm in as you fill. Container-grown plants simply need the top of the compost matching with the soil level. After planting, sprinkle a general purpose fertilizer such as blood, fish and bone over the surface of the soil.

Cordons can be planted much closer, giving you the opportunity to try a couple of varieties in a relatively small space. They will need wire supports – grow them up against a fence onto which horizontal, galvanised wires have been stretched at 30cm, 60cm and 90cm intervals from the ground. Tie the main stem of the cordon gooseberry loosely to a bamboo cane and tie this in to the wire supports. Leave 40cm between each cordon and 1.5m between rows.

Care:

While you will struggle to kill off a gooseberry, it will take a little attention to guarantee a bumper crop of up to 5kg per bush. Begin the season’s care by adding a fresh sprinkling of organic fertilizer in February, then topping up with a layer of organic mulch in March, taking care it doesn’t touch the stem. Making this last addition at least 5cm thick will improve moisture retention in summer months – essential to help the berries swell properly – and will slowly feed plants over the growing season as it rots down or is taken into the soil by earthworms.

Watering is important, especially in early summer when the fruits are developing. A sudden wash of water applied after a prolonged dry spell will see berries swell quickly to split the skins – a sure-fire way of increasing disease risk. From the end of May it’s advisable to remove about half the fruits to give the remainder enough space to grow on properly. The thinned berries needn’t be discarded – use them for cooking. This process may be completed in stages.

Plants require protection in two ways. First you may need to cover them over with horticultural fleece at flowering time to avoid frost damage. Draping the material over bushes will be all that’s required, but remove it by day so pollinating insects can do their bit. Birds can be a nuisance in some areas and will peck at mature berries. If you haven’t got a fruit cage to keep them off then support netting tightly over bushes. Weigh down the edges with stones so that blackbirds can’t creep in at ground level to snaffle your crop.

Harvesting:

Gooseberries are relatively early to produce their haul of juicy berries. Thinning in May will give the first fruits, though this process can be carried out in stages until they are well spaced, allowing those that remain to get progressively larger. Mature goosegogs will be ready to take from June onwards, with the latest-fruiting varieties cropping in August. If you want to prolong your enjoyment of this obliging fruit then plant early, mid and late-season varieties to give the widest possible harvest window.

Dessert gooseberries are best picked minutes before enjoying them, when they will be at their peak of both flavour and goodness. However, they will keep for over a week in the fridge and gluts are suitable for freezing. When picking the fruits cut them free with the little piece of stem that joins them to the plant. If you simply rip them off, the skin will tear and the gooseberries will not keep for nearly as long. Your harvest can be used in so many ways – but it’s hard to beat the heavenly experience of fresh dessert berries folded into Greek yoghurt with just a drizzle of honey.

Pruning:

The object of pruning your bushes is to encourage a balanced, open structure and plenty of vigorous growth. This will in turn improve air circulation and reduce the opportunity for diseases such as American gooseberry mildew to gain a foothold.

Formative and maintenance pruning is best carried out in late February, just before plants burst into leaf. This has the advantage of keeping them naturally protected from bullfinches, which devour winter buds – the plants’ spines help to form an impenetrable barrier. A second, summer pruning around June to early July sees all new sideshoots reduced to just five leaves. This allows more light into the bush to help any fruits ripen, and maintains a healthy airflow.

Start pruning by selecting four or five of the strongest shoots on one-year-old bushes and reducing these by a half to three-quarters. Cut out any stems coming from the leg, and surplus growth back to where it is emerging. The nursery may have completed this initial pruning for you. The following February, cut back new growth by a half, aiming to leave eight to ten of the strongest branches in place to create a pleasing goblet shape to the bush. Prune back all other shoots to where they emerge, making cuts just above a bud. In subsequent winters, prune new growth back by half and cut out any excess branches to keep an open, even shape. Snip back laterals to two buds.

Cordons are pruned at the same time by reducing the previous season’s leader shoot growth by a quarter, which will stimulate more fruit-bearing sideshoots. Those from last year should be cut back to just two buds to maintain the columnar shape.

Citrus Fruits

Posted on by

Conditions:

All citrus need warm conditions in order to thrive, although they can cope with surprisingly cool temperatures so long as they are not over-watered and have plenty of ventilation. Some daring growers with advantageous microclimates have even been able to grow the hardiest citrus trees outdoors all year round. If you want to try this, you will need to have a south- or west-facing brick wall that will radiate back any stored heat from the day to the plants at night. You will also need to be living on the west coast where the influences of the warming Gulf Stream are at their peak.

Otherwise, check that you have a suitable home for your citrus for both the summer and winter months. If you don’t have a frost-free greenhouse or conservatory, it is possible to keep your plants in a bright position indoors. If you want to do this, you will need to make sure that the humidity is kept high (see box, ‘Overwintering’). You’ll find that the sweet-scented flowers, glossy leaves and colourful fruits have considerable ornamental appeal when grown under cover throughout the cold weather and outside on the plot in summer.

The other major consideration when cultivating citrus is the compost. The plants need a nutrient-rich growing medium that is also free draining, as they can’t abide waterlogged or excessively damp roots. Buy some purpose-made citrus compost or create your own. For a homemade citrus compost combine four parts loam-based compost, such as John Innes No 3, with one part drainage material, such as bark chippings, perlite, horticultural grit or sharp sand. This mix will achieve the ideal balance of moisture retention with good drainage

Planting:

All citrus crops are best grown from bought-in plants, and a number of specialist nurseries have sprung up to supply a dizzying selection from which to choose. These are available at any height from 15cm tall to a mature tree. Most varieties will have been grafted onto a rootstock, which will limit their ultimate size and make them suitable for container culture. Smaller plants will take longer to reach the fruit-producing stage but will be more adaptable and likely to settle in quickly. Larger types will be ready to crop immediately, but will cost considerably more to buy.

Plants can be bought and planted up at any time of the year. Pick a container that is only slightly larger than the one your citrus arrives in; about 5-10cm wider and deeper is perfect. It is better to pot on in stages than to ‘swamp’ a plant in too large a tub. Ensure there are plenty of drainage holes and prop it up onto pot feet so that any excess water can escape unhindered from the base. Place a few crocks or stones into the bottom of the container before adding some of your compost. Position the citrus rootball on top of this and infill around the edges, pressing down on the compost as you do to remove any air pockets. Thoroughly water-in the newly potted plants to further settle the soil and top up with more compost if necessary.

Growing:

Position citrus plants in a bright and warm position. During the summer, they will love being outdoors where the access to fresh air and higher light levels will give them a real boost. Any pests that have built up under cover, such as scale insects, will clear up once the plants are moved outside. As mentioned, a sunny, sheltered patio is ideal – the extra warmth will encourage fruit formation. Plants can be moved outside from May, as soon as the possibility of frost has passed.

Citrus need very little pruning, but some formative work on young specimens will help them achieve a desirable shape. Remove lower branches to the main stem so that you encourage a single, clear trunk. Any badly placed, excessively long branches or those that are damaged or diseased may also be cut right back. Do this in spring, just as the trees are starting into growth, and use a sharp, sterile pair of secateurs for the job. Additional pruning can be carried out as needed during the growing season.

Once your tree is mature, almost no pruning will be necessary but unproductive branches can be removed, as should long, straight stems emerging near the base of the plant, known as ‘water shoots’. Very long and flexible branches can be tied down to the main stem to encourage fruit production in a technique called ‘festooning’.

Care:

Watering with consideration is essential and different times of the year will dictate different approaches. The trick is to keep plants moist in the summer, but never wet. In the winter, when temperatures are low and plants are growing very slowly, watering sessions should be dropped back to just once or twice a fortnight so that the compost almost dries out entirely in-between.

Container plants will need regular feeding if they are to flower and set fruit successfully. Special citrus feed is available, but during the growing season it is also possible to use a liquid tomato feed or liquid seaweed solution. Apply this every week or two, according to the instructions. Established plants will need to be potted on into the next size of tub as soon as the roots reach the base of their existing pot. Do this in winter and use fresh compost around the sides. Once the container size reaches 60cm in width and depth, it will be tricky to pot your citrus on much further. To give such plants an additional boost, scrape back the surface layer of compost from the pots each year in late winter and top-up with fresh compost mixed with a little general purpose organic fertiliser that is rich in trace elements.

Pests can become a nuisance under cover where the air is still. To counteract this, provide optimum ventilation – even during the winter (so long as it isn’t too cold outside). Aphids, scale insects and whitefly may be suppressed under cover using ‘biological controls’ – these are predatory insects that can be introduced to feed on the pests. Alternatively, you could spray the plants with a homemade soapy solution. These problems usually disappear when the plants are moved outside for the summer. If you want to keep them under cover all year, regularly damp down the floor and provide some shading during the sunniest, hottest months.

Harvesting:

Citrus fruits take up to 12 months to mature, the exception being grapefruits which take even longer! For this reason, it is quite normal to have both flowers and fruits at different stages of growth on one plant. Young plants should only be allowed to set four fruits, but older ones can be left to produce as many as they can – any excess will naturally drop off. The heaviest crops are achieved when average night-time temperatures are above 16°C for the six months following flowering in spring. If you want maximum fruit production then you may need to supply additional heat in early autumn when plants are brought back in under cover.

Consider supporting heavily-laden branches and pick your crops as soon as they are the right size and colour. Ripe fruit may be left on the plant for up to two months without deteriorating, and this is the best option to maintain their juiciness. Cut them away using a sharp knife or a pair of scissors, taking care not to pierce the branches.

 

Blackcurrents

Posted on by

Conditions:

A sheltered spot with a reasonably fertile, moistureretentive and well-drained soil is preferable for blackcurrants. If it has a slightly acidic pH (around 6–6.5 – testing kits are cheap and widely available) that’s all the better, but it’s not essential. Avoid placing them in frost pockets, as a late frost can damage the flowers and lead to a smaller harvest.

Although blackcurrants will tolerate partial shade, the fruits taste better when exposed to plenty of sunshine, and shaded bushes may become weak and leggy. A few weeks before planting, always clear the ground of weeds, especially perennial types such as dandelions or docks, and enrich the soil with plenty of well-rotted manure or compost.

Planting:

Most blackcurrant bushes are sold as bare-rooted plants and the ideal time for getting them in the ground is late autumn to early winter. Any time up to mid-March is also fine (as long as the ground isn’t waterlogged or frozen) but they will have less time to settle before starting into growth. Container-grown specimens can also be purchased from garden centres or nurseries and planted throughout the year – but whenever possible, opt for the autumn, early winter or spring. Whatever the month, planting should always be avoided if the ground is very dry, frozen or waterlogged due to heavy and persistent rain or poor weather conditions. For the best results, select bushes that are certified as virus and disease-free and have at least three obvious stems.

Space the bushes 1.5m apart in the ground, and set them about 5cm deeper than they were planted in the nursery – an obvious soil mark is usually visible on each plant. This will encourage the stem bases to form roots as well, and eventually give the bushes more support.

Once the new bushes have been planted in the ground, it’s absolutely essential to water and firm them in well. A 7.5cm-deep mulch of garden compost or well-rotted manure should be spread around each plant – this will help to feed the blackcurrants and keep down unwanted weed growth. At this stage, the main stems also need to be pruned to two buds from ground level (these buds should face outwards rather than inwards as that’s where you’ll want your fruit to appear). The reason for this is to channel the plants’ energies into establishing the root system in the soil and encouraging the production of lots of healthy new stems (from above and below ground) in the spring and summer. It’s these that will produce the first crop of fruits the following season.

Growing:

New and established blackcurrant bushes must be kept wellwatered during long spells of dry spring and summer weather, and weed control is vital all year round. However, the plants have a wide-spreading, shallow root system and so using a spade, fork or hoe around them could mean you can damage it accidentally; a combination of hand weeding and mulching is less likely to cause damage.

For bumper crops, feed the bushes with an organic fertiliser (applied at a rate of approximately 100g per square yard) in the early spring and top-up the mulch of compost and manure around each plant every April. The plants can also be given a boost by applying an organic liquid fertiliser when the fruits are starting to swell in the summer.

Care:

In harsh winters, the roots (or rootballs) of new bushes can sometimes be lifted out of the ground by hard frosts. If this happens, firm them back in immediately. The flowers of some varieties (notably older types) are prone to cold damage and, if a frost is forecast while they are blooming, it is a good idea to carefully drape horticultural fleece over the bushes.

Unfortunately, currants are sometimes sought out by hungry birds and the developing and mature fruits may need protecting by covering with a sheet of fine netting. Alternatively, dangle old CDs from string nearby or hang thin strips of recycled tin foil from the stems – these will glint in the sunlight and rustle in the slightest breeze to frighten away any passing birds.

Harvesting:

Blackcurrant fruits are ready for picking in the mid to late summer (July and August) and are at their best about seven days after they have turned blue-black. They can be gathered individually or, if you want them to stay fresh for a little longer, you can harvest them as whole trusses. If possible, pick the blackcurrants in dry conditions, as wet fruits often don’t store well and may turn mouldy. The fruits can be eaten immediately, or stored in a fridge for one to two weeks. Alternatively, they can be frozen for eating later – they should last at least six months this way.