It's not easy to shop for someone, whose garden looks perfect. It seems as though they have everything. However, there is something new that we get every year, we never seem to have enough of, vegetable seeds. There's nothing more fun, to us, than trying something new; Nurturing a new plant from a tiny garden seed, and watching it turn into a colorful vegetable harvest, happens to be very fulfilling to us. So, if you want to give a gift that is well received, and won't sit uselessly in the back closet, then pick out some weird, and fun looking, heirloom seeds.
Even if they have tried a certain seed variety before, they'll still appreciate a new stock, of fresh viable seeds. The bonus to you is, not only can you pick out several items, for a relatively low price, you may just end up with some free, tasty vegetables, at the end of the year.
If you are not into vegetable gardening, then you may be surprised at the crazy stuff that is out there. Go with your gut, on the heirloom vegetable varieties, they would want to eat. The Pink Thai Egg, for example, is the only tomato I know, that actually taste like there's a hint of cheese on it. If it ripens to a dark pink, past its initial, pastel pink hue, it tastes like a really sweet tomato, with feta on it. Talk about a cool gift to give a gardener.
If you are still hesitant on picking out items yourself, you can always send them a gift card, and let them choose their own present. Either way, they'll be happy you did.