Read them in order or jump to what you need — every word is free. On a real plot, you unlock the hands-on practice for each area by proving the one before it.
Put a seed in the ground and keep it alive — the four needs, seeds vs transplants, depth, spacing, watering.
Feed the soil, not the plant — texture, building a great mix, compost, N-P-K, pH, and keeping soil alive.
Know the antagonists and deploy the counters — prevention, friend vs foe, and the least-harm ladder.
New classes are added as the community masters the basics — each one a self-contained expansion, slotted into this same system. The knowledge stays flat and free; what you earn on a real plot is the hands-on practice.