I always remove these suckers, they detract nutrient from the rest of the
plant. The cobs which may form on them will be inferior anyway and will not amount to anything. Best to cut them off.
To get a better number of cobs per
plant, (my best is 5 off 1
plant, average is 3), wait until the secondary roots develop , that's those big ones that come out from the base of the
plant, often above ground level. Once these roots are
growing, bury half of the stalk in compost, well rotted manures and mulch. So if your
plants are a metre high, you can put half a metre of goodies under them. This will feed the secondary root system which is capable of taking up large amounts of the good stuff. They also require plenty of water for this to work properly. Normally you would expect this to rot the stems on most
plants but on sweet corn that is not the case. It will also be a great additive to the beds for the following crop.