Agriculture is a very wide field, they are different ways to go into agricultural business:

1. Crop cultivation
2. Animal husbandry
3. Feeds business
4. Equipment leasing
5. Financier
6. Land renting
7. Consultant
8. Production of packaged products
9. Production of juice and jam
10. Agro chemical business

for more details http://naijasphere.com/10-agricultural-business-to-make-profit-from/

Best agriculture businesses: https://www.practicalbusinessideas.com/money-making-agriculture-business-ideas/

What about hibiscus flower storage business! Its also a good business.

Last season price start at #115,000 per tonn and now hibiscus popular know as zobo go as higher as #500,000 per tonne.

Season start by november

Read the full details here http://davidprof.com/blog/hibiscus-flower-storage-business/