Off-farm work is becoming more important for small farmers in Kenya, but it can reduce the amount of fertilizer they use on crops like maize and vegetables. This is because the money earned from off-farm work is often used for other things instead of investing in fertilizer. However, off-farm work doesn't affect fertilizer use on tea crops. This shows that there is competition for resources between farming and non-farming activities, which can impact how much farmers invest in their land.