PlantFiles: Crimson Clover, Italian Clover
Trifolium incarnatum

Crimson Clover, Italian Clover, Trifolium incarnatum is a Naturalized plant in Texas.

Used mainly as a cover or green manure crop for which it is excellent.

Crimson clover has so many good things going for it, I consider it to be absolutely indispensible. I'm always surprised more isn't said about it, so here goes:
I plant it in the fall as I clean up the vegetable garden for the winter. It's growing season can almost perfectly match the veggie gardener's off season.
C'clover fixes between 70-150 lbs/acre of Nitrogen from the air, and while decomposing it releases this and all the other nutrients it's kept in play over the winter to your crops. Rather than the land lying fallow and nutrients slipping away, in the spring you have a soil absolutely teeming with life- especially earthworms. I was dumbfounded to see how many it drew my first spring (6-10 per spadeful, it was almost creepy to see so many wriggling things), but then even more ladybugs and honeybees started showing up and the earthworms became a minority.
In midwinter when everything else is various shades of brown and grey C'clover is as green as a field of emeralds and has a rich lush smell. It's almost worth planting just for that smell.
In spring thousands upon thousands of crimson blossoms saturate the garden- its fantastic! I Take some pictures and let the bees work the blooms for a week or so-the prime planting time for warm season crops has arrived and the clover is about as full of Nitrogen as its ever going to get. Chop it up, plow it in shallow, and plant crops.
Plant a huge meadow of it or just a massive flower bed, it's plenty cheap.
In a meadow or pasture it will reseed itself pretty reliably and naturalize if you don't mow it too often, but for that purpose you should plant it in the regular warm growing season.
Though Trifolium Incarnatum grows unusually well in the colder months, and can take most frosts/snows here if it isn't too mature and succulent when they arrive, big patches of it will die off with the rest becoming real prone to diseases if it's planted too early. Aim for getting it well established but not quite luxuriant by a little before your first hard frost (~15 degrees at night for me). Another drawback it has are aphids, but they are the reason it draws so many ladybugs I guess.
Crimson clover is available from several mail order places for more expensive (but perhaps highter quality) seed, or locally in bulk from various farm and agriculture suppliers (Farmer's CO-OP is where I get mine)
Replenishes your soil, supports beneficial insects, cheap and abundant, gorgeous show of flowers, blocks some weeds out, forage for your animals, naturalizeing N source for your land, and can grow through a modest winter zone6 and south. I love it. (can you tell?)

An annual trefoil from South and Western Europe which is widely naturalized.

Has typically trifoliate (each leaf is 3 lobed), wedge shaped, slightly toothed, lightly downy, mid green leaves. Bear oblong to cylindrical flower heads where tiny red flowers are clustered. The flowers may very rarely be white.

Flowers in the main May-July but can go on well into August.

Likes a moist, well drained, neutral soil in full sun.

Being a legume, it is used as a cover crop for some organic systems and is ploughed or dug in just before flowering.