Allotment seeds

Allotment seeds are used to grow fruits and vegetables in allotment patches.

The following fruits and vegetables can be grown in any allotment:
 * Potato at level 1,
 * Onion at level 5,
 * Cabbage at level 7,
 * Tomato at level 12,
 * Sweetcorn at level 20,
 * Strawberry at level 31, and
 * Watermelon at level 47.

Each patch requires three seeds of the same type to begin growing that fruit or vegetable type