Grow sweetcorn in your back garden

Carrots have it. Peas have it. Parsnips certainly have it. But there’s no vegetable to rival sweetcorn, for pure sugary sweetness. Modern super-sweet varieties taste tooth-crumbling sugary and for this reason children love the stuff.
The plants themselves have a jungly sunflower fascination, great for late summer garden height without the need for painful DIY supports. For some reason they remain a peculiarly British and American treat while on the continent they cling to the idea that it is little better than cattle feed – our gain!
With a few simple rules anyone should be able to conjure a crop in their back garden. A sunny, sheltered spot, never planting out until after the frosts, and an early-maturing variety will all contribute to sweetcorn success.

Plant care
By July, sweetcorn plants should have been outside for a month and growing on smoothly. If you’ve missed the boat this year, you might still be able to pick up a few plants at garden centres at the beginning of the month, and squeeze in a late harvest, if the autumn is kind and they get the best sunny spot.
Plants that went out after the last frosts should be gaining height fast. This is the time to keep an eye on water levels – a dry spell can really stunt plants so be prepared to give them a liberal soak. Adding plenty of well-rotted organic matter the winter before (or at least at planting time) will help the soil retain moisture in future months. Adequate moisture is especially crucial when the kernels start to swell and happy plants should yield two or three well filled cobs.
If you suffer from a free-draining soil, then mulch plants to retain as much water as possible. This will also help keep plants weed free, and if you’re in a windy site, earthing up the stems will minimise the occasional risk of plants toppling over. If you didn’t add a general purpose fertiliser at planting, then scatter one between the plants now and hoe in (alternatively use a liquid fertiliser once the cobs begin to swell). Just watch out when hoeing not to damage the sweetcorn roots that spread just below the soil surface.

Plant partners
Some people advocate the three-sisters combination: sweetcorn, squashes and climbing beans all grown together. Personally, I advise caution. Yields of each plant are naturally less than if they’d been grown in isolation, although it does allow you to squeeze a greater diversity of crops into a smaller area.
The main issue is harvesting – the sweetcorn must be planted widely enough to reach the courgettes/squash scrambling between their pins. Add to that a jungle of beans strangling each stem and harvesting turns into a severe logistical problem. If you are short of space, then make sure the soil is in excellent heart and try a couple of squashes towards the edge of the block but keep the beans for somewhere else.

Pollination
Sweetcorn is an uncomplicated crop to grow, but there is one potential stumbling block – pollination. Sweetcorn is wind pollinated, the male flowers at the tip of each plant pollinate female flowers half-way down the stem (these are the ones that turn into cobs), using the whim of an air current as their means of transport. If you plant your sweetcorn in a single long line, and the wind is blowing across the line, then pollination is going to be pretty poor, which means disappointing, gappy, unpollinated cobs. The solution is to arrange plants in blocks, with 45cm (18in) between each plant. You can also try tapping plants once the male flowers are open to release the pollen.
One other pollination detail to bear in mind is that, if you’ve chosen a super sweet variety, you’ll need to keep it isolated from standard types. Cross-pollination will lead to a drop in sweetness, so if you have different varieties that mature at the same time you’ll need a distance of at least 8m to be safe. Alternatively, pick varieties that ripen at different times.

Harvesting and cooking
Speed matters with sweetcorn. It’s often said that your saucepan’s water should be at a rolling boil before you even think of stepping outside. From the moment the cobs are picked, their sugar starts to be converted into starch and sweetness consequently falls, so only pick when you’re ready to use them.
A sure sign that cobs are ripe is when the tassels turn from cream to brown, usually in late August. To make thoroughly sure, simply peel back the outer leaves at the tip and press a nail into a kernel. If the liquid is clear it’s still unripe; milky and it’s time for dinner. You should be able to twist the cob from the main stem with ease without damaging the plant and the chance of subsequent cobs. Boil or steam for a matter of minutes and enjoy.
If having friends round for a barbecue doesn’t use up a cob surfeit then you can always pop them in the freezer. Either blanch the entire peeled cob for five minutes before freezing whole, or strip the kernels with a knife, blanch, bag and freeze. You’re left with frozen little bursts of summer to brighten winter.

Baby corn
If you’re chasing crunchy raw baby corn to use in dips and stir-frys, then you’ll need to seek out different varieties such as ‘Minor’ (T&M), and grow plants in a slightly different way. For baby corn you’re aiming to pick cobs before they have been pollinated and start to swell,
ie when the tassels have just emerged and are still cream. Plant around 20cm (8in) apart and you should get around four small cobs per plant.

Top Tip
Fancy trying something entirely different? Sweetcorn ‘Red Strawberry’ (T&M) has tiny strawberry-shaped cobs. Simply harvest when the entire plant (they only reach around 1.2m/4ft) has browned, then finish drying in cool, airy space such as the shed or a spare bedroom. To cook place the whole cobs into a microwave to explode into fluffy white popcorn.

Varieties
New varieties come onto the market with impressive regularity, so don’t be afraid to experiment, especially since new varieties are often better suited to cooler UK conditions. If you have the space then try a couple of varieties that mature at different times, or simply do two sowings of the same variety, a month apart.
Here are some to look out for.
 ‘Swift’ – Living up to its name, this is an early maturing variety that’s a handy choice in cooler climates, plus their shorter stature suits them to more exposed sites. Very sweet and tender cobs make it a firm favourite. (POD/Marshalls)
 ‘Northern Extra Sweet’ – Another super sweet variety producing long cobs on plants that reach only 1.5 to 1.8m tall (5-6ft). (T&M)
 ‘Lark’ – A good garden variety with sweet, thin skinned cobs that are early to crop. (Unwins, T&M)
 ‘Honey Bantam Bicolour’ – Exceptionally early variety with bicoloured kernels; golden yellow and pale cream. (T&M)