So, I don't believe putting lines of fertilizer in a desert would make a field... Anyone an expert?
1. There's the wind blowing it away, blowing sand all over, wrecking everything.
2. There's nothing to contain water, there's an oasis a bit away (don't know how that works) but it's not like they made a box under the fertilizer.
3. That sand is not soil so I guess their fertilizer is also sufficient as soil? They'd need a shit load and calling it fertilizer sounds kinda wrong if that's the case. Fertilized soil I guess would be the term to use...
I don't really feel like you can explain this away with life or sand magic tbh.