There are other organic systems that can work well in the tropics. The best known is the Forest Gardens approach. In Forest Gardens, a combination of useful plants that work well together are grown in one plot. For example, there may be a level of tall fruit trees, then lower trees or bushes that like some shade (maybe coffee), then vegetables. The different plants have to be selected so that they support each other (rather than compete). Legumes, such as Inga, can be included. This system has been successfully employed, particularly by Trees for the Future2
Both systems have advantages and disadvantages. The special advantages of the Inga system are:
- It is cheaper
- It is simpler
- Requires fewer different resources, just Inga seeds, whereas the forest gardens require a set of the appropriate different plants
- There is less to learn than for Forest Gardens, therefore fewer field instructors needed
- All this means Inga will be easier to roll out in quantity and
- Inga is likely to spread more easily from farmer to farmer
- It is more suitable for larger scale planting of crops like maize
The Forest Gardens may allow for more variety of plants, such as fruit trees, to be in the system and will be better for crops that grow for several years. The Inga system is better suited to annual crops.