What actually makes a good gardener gift for your brother?
Start by eliminating mismatches: generic plant kits that ignore climate, space or the plants they already know how to grow. Then narrow the list around well-made hand tools, propagation gear, plant-care upgrades and useful items suited to the space they actually garden in. Because this is for your brother, keep the interests you know he will immediately recognize as “his thing” in mind and avoid generic sibling jokes that replace rather than support a real gift idea. A small but precisely matched upgrade can be more memorable than a larger generic present.
The strongest gift ideas usually come from the person’s real habits: what they already use, what they talk about and what would make an existing interest better.