Guest Articles

"Love your sweetcorn" -an article by Mick Ryan New North Road Did you know that maize, or sweetcorn as it is more commonly known in the UK, is one of the oldest cultivated crops in the world? Originally grown a food crop in Mexico some 7000 years ago it's cultivation spread across  the Americas and, after European colonization, throughout the world. Now it is the staple food crop in many parts of Africa and Asia. These days, in much of Europe and North America it is mainly grown for animal feed, for food processing(cornflour) and the manufacture of cornflakes and popcorn. In the USA and, of course in the UK, sweet varieties of maize are also enjoyed as "sweetcorn" or "corn on the cob". For those of us lucky enough to have our own allotment plots sweetcorn can be enjoyed at its best - straight from the plant. The cobs rapidly lose their sweetness after harvesting as the natural sugars turn to starch. Sweetcorn which has sat on a shop shelf for two or three days just can't compare. In order to successfully cultivate sweetcorn it is important to understand the special needs of this unique plant. Plenty of sun, regular watering and well drained, nitrogen rich soil give the best results. Dig in plenty of well rotted compost, or grow on raised beds if you prefer. Sweetcorn also requires intense pollination. By this I mean that you can't just rely on passing bees to do the job. You've got to roll up your sleeves and give them a hand. Let me explain. The bulbous cobs, known as "ears" which appear on the stems just below a leaf have a little tuft of hairs, known as "silks" growing from their tops. These are the female flowers. Each strand represents one seed of sweetcorn and every one has to be pollinated individually to ensure a complete head of corn. If only half are pollinated, then only half the seeds will form and the cob, when cooked will look ugly with grey bald patches here there and everywhere. The pollen comes from the male flowers, known as "tassels" which appear like a little palm tree on the very top of the plant.  Bees and other insects disturb the tassels as they go about their business collecting pollen and some of the grains float down onto the plant below. A few will  land on the silks and pollination occurs. Maybe this works satisfactorily in hot subtropical climates where there are abundant flying insects to do the job but here in the UK the plants may need some help. Once the silks start "browning up" no further pollination can take place so you've got to move fast. The way we help the process is by firstly growing the plants close together, about two feet apart and once the tassels have formed, regularly tap the stems to release pollen. This is best done on warm days when there is no breeze when the silks are most receptive and the pollen won't blow away. Towards the end of the pollination period you can carefully break off a few tassels, which are not directly above any cobs and brush them across the silks. It is also a good idea to grow a flowering companion crop between the plants. More of this below. The Three Sisters The value of beans cannot be overstated. There few plants which can so efficiently capture nitrogen from the air and "fix" it into the soil. Sweetcorn needs  nitrogen to thrive but can only absorb it from the soil so it is a very good idea to plant beans between your sweetcorn plants. Any variety of beans will do but I prefer french beans, standard and climbing varieties. Plant the standard varieties after the sweetcorn has become established and climbing varieties when the sweetcorn is about waist high so as not to overwhelm them and hinder the pollination process by covering the silks or tassels. Another "must"  for sweetcorn is to never let it dry out. Obviously regular watering is top of the list but it is also a good idea to grow a green mulch to shade the bottom of the sweetcorn plants and to stop the sun drying the soil. Traditionally squashes are used, but courgettes or melons will do just as well. Personally I don't like squashes and there are only so many courgettes you can give away before you neighbours start hiding behind their curtains every time you pass by their houses. Melons need more attention than the others and may not do so well. Whatever you do don't grow melons and squashes together. They can cross pollinate with horrible results. My personal preference is to grow a ground cover variety of nasturtiums which have abundant flowers and make little demand on the soil. This method of complimentary companion cultivation is known as "The Three Sisters" a title which has passed down through the ages. Varieties Not all maize is grown to be eaten as a vegetable of course and increasingly varieties such as "white maize" appear on allotment sites, which are  flour varieties. Flour varieties are high in starch and low in sugar and can be problematic insofar as cross pollination can easily occur causing the sweetcorn varieties to produce cobs of poor flavour. To avoid this it is important to check with your allotment neighbours  what type they are growing. If they are growing a flour variety, or you are not sure, plant your own sweetcorn as far away as possible and you should be OK. Be wary of accepting seeds of unknown origin for the same reason. You may see many super sweet varieties advertised on the internet but beware, these may be unsuitable for our climate. As a general rule of thumb, the sweeter the variety, the warmer the soil needs to be at the time of planting. As usual, the safest option is to buy appropriate seed from a reputable British supplier. Finally, a tip for those who prefer to grow in rows rather than in bunches or beds. Sweetcorn grows "two dimensionaly" by which I mean the leave and cobs all grow left and right so that it is possible to determine when first planting out the young plants how they will look as adult plants, so by planting "leaf to leaf" you can optimize space between rows making it easier for watering, tapping and of course, picking those beans!
Add your one line caption using the Image tab of the Web Properties dialog New North Road Allotments Home Shop Faq News Things to do Plots Contact Articles Articles