If you don't have enough (or good enough) pasture for your rabbits but you still want to raise them without pellets you will have to grow their greens for them unless you want to spend a fortune buying greens from the grocery store.
And since each adult rabbit will need around a quart of leafy greens a day you want something that is easy to grow and produces well. Below are some of our favorites to grow for our rabbits, organized by approximate season of harvest.
Early Spring
Kale
Another leafy green that rabbits love, kale is loaded with vitamins is also easy to grow. Lacinato is a popular variety to grow, this year we are growing red Russian kale as well, and I think it gets a bit bigger than the Lacinato kale.
Radishes
The fastest leafy green crop there is. Rabbits aren't very fond of the roots, so plant them densely about every two weeks for a continuous harvest.
They won't grow very significant roots when planted so close together. So, if you want the roots for your own use you will need to thin them. You can harvest the leaves like you would leaf lettuce for a longer harvest or you can pull the whole plant up.
Spinach
Spinach doesn't produce as well as other things, but it is easy to grow and rabbits like it.
Dill
Dill is good to have in your garden even if you don't have rabbits as it deters some pests.
Late Spring-First frost
Basil
We have fed so much of this to our rabbits! Basil is super easy to grow, produces well and is also thought to be a natural coccidiostat (something that prevents or cures coccidiosis, a highly contagious parasitic disease).
It self-seeds easily, so if you let some of your plants go to seed at the end of each growing season you will probably never have to plant it again. It can also be dried and fed during the winter.
Chard
Chard is one of the only leafy greens apart from herbs that will grow through the heat of summer without extra care.
Squash and Cucumber Leaves
Not as well liked by all rabbits as other greens, but since they grow so fast (squash more than cucumbers) it's worth seeing if yours will eat it.
Cilantro
Another easy to grow herb that is great for human consumption too!
Fall
All the plants that can be grown in the early spring can also be grown in the fall.
Winter
Unless you live in far south Texas, Florida, or California, there isn't really anything that can be harvested outside during the winter. You can try growing any of the smaller plants either under grow lights in your house or in a greenhouse.
Other Plants You May be Growing That Rabbits Can Have
Bean Leaves
Pea Vines and Leaves
Carrot Tops
Parsley