HOW TO GROW SWEET CORN FROM SEED
It’s hard to beat the taste of a freshly picked and timely cooked sweet corn. In fact the very thought of a home grown cob - boiled to perfection and drizzled in butter - is enough to make your mouth water. Of course, the only way to assure such a culinary delight is to grow your own because freshness is the only guarantee of quality flavour. In fact some say that there should be no more than 10 minutes between picking and cooking!
In northern European climates, the seed can be started off under protection from mid April onwards with a view to planting out from the end of May up until the middle of June. Of course, planting out will all depend on how late the frosts are in your area because your sweet corn crop will be lost if it is hit by a late frost. Secondly, planting out into open ground should really wait until outside temperatures are consistently reaching at least 16 degrees Celsius during the day. If it is colder than that then the crop could be at risk from fungal disease.
.Sowing Sweet Corn
To ensure an early crop, sow sweet corn seed - either indoors or in a heated greenhouse – around about mid April. Using modular trays or 2/3 inch pots, fill with a good quality compost such as John Innes ‘Seed and Potting’, then sow two seeds into each unit covering them with a good inch of compost. Water well and if they are being germinated indoors - move to a warm, bright windowsill. If you are using a heated propagator or greenhouse then the temperature will need to be kept at approximately 18 – 21 degrees Celsius.
The sweet corn seedlings should germinate after 10 – 12 days, and once they have fully emerged the weakest seedling from each pot should be removed. If they have been germinated in a propagator the lid can also be removed and the temperature turned down to 16 degrees Celsius. However they are being grown, do not allow the compost to dry out or to become waterlogged as this can increase the risk of fungal infection.
The young sweet corn plants, and be planted into their final positions once all danger of frost has passed – around the middle of May, but remember that they will need to be hardened off for a week or so before hand. This can be achieved by either bringing them back under protection over-night or placing them under a cloche or poly-tunnel outside.
Unlike many of our common food crops sweet corn are wind pollinated so once they are hardened off - and ready for their final position - they will need to be planted into block in order to ensure good pollination. Poor pollination will only result in a poor crop!