We live in an age when premiums are placed on local and organic food, but no matter what a restaurant menu or label says, you really can’t do better than growing food yourself. Many of us don’t have the outdoor space to cultivate a well-stocked garden, but that doesn’t mean it’s not possible. You don’t need fertile beds of well-cared-for soil, and you don’t even need the outdoors at all—just some food scraps, a window sill, and water.

Food52 has a round-up of a few of the best regrowable veggies that only take about a week to replenish. Generally speaking, you just need an old root to yield an entirely new set of kitchen crops. With romaine lettuce, stand the butt of a stalk down in a cup or bowl with a little water, and watch it bloom—same goes for scallions and fennel bulbs. And while you may never have eaten carrot greens, they too can grow in your house by just lopping off the top of the root vegetable and placing it in some shallow water. (Any root vegetable greens can grow this way.)

The theme here, as you may have noticed, is sunlight and water—just change the water when it gets dirty and harvest as needed.

A lot of other crops can be grown in this manner, but they take longer. Veggies like celery, lemongrass, bok choy, basil, ginger, garlic, mushrooms, and bean sprouts are among these regrowable veggies. Others that take a lot longer (read: are maybe not worth it) include potatoes, onions, pineapple, and—brace yourself—avocado. Even if you’re not ready to fully commit to the alligator pear, water-grown vegetables are a good way to save some money, flex that green thumb, and continually appreciate the regenerative power of Mother Nature.

[h/t Food52]