With current market conditions, where we have a surplus of white maize, it might be a better investment to hold on to your current crop then to sell at spot levels.  The South African market is currently trading in contango. The market in the new season (not planted yet) is trading at a higher price than the old season. Giving an investor the opertunity to carry his maize for free into the new season. 

This decouraging the sell of maize in the current season, and incouraging carring maize to the new season. Descouraging producers to sell at current price levels.

If this continious it would put a serious constrain on the new season, espesially exports.

With the co-ops offering  year storage for maize currently between R94 and R114 a ton.

One can in practice take delivery at the current price level carry it for a year and give delivery again, and enjoy on average an increase on your capital of between 6.5-8%, depending on your year storage price. This will interst can increase should you be able to store your maize cheaper, for instance in silo bags.