If you come across a bag of ranunculus corms at your local nursery and the picture on the bag is stunning (they are!) but the spidery looking lumps are just creepy (or worse: intimidating), let me assure you that they are worth the risk! Ranunculus can over winter in our mild Texas weather and use the cool chills to develop a robust root system, giving delicate, layered, colorful flowers in early spring, just when we're all tired of the mud!
Ranunculus have the best chance of growing if you pre-sprout them first. Get a bucket of water deep enough to submerge the amount of corms you have. It's important that the bucket be very clean, bacteria is never good when it comes to flowers. Then soak the corms for 4 hours. Leave the bucket under a constant drip or put an aerator from a fish tank in the bucket - you want constant movement in the water to prevent rotting. In 4 hours, the spidery corms will plump to twice their size. Fill a tray or box or crate with moist potting soil and bury the corms gently, they can be close together but not touching each other. The potting soil shouldn't be too wet so that it clumps, that will produce rot, but you do want some moisture in it. Then place the box in a cool dark environment for 10-12 days. Check it occasionally to make sure the soil didn't completely dry out and wet it a little if needed. Honestly, we just make sure our soil is moist and then we neglect it - haha! Farmers don't often have extra time to check on things. :p We used our unheated garage and it worked fine even with a couple 80' days thrown in there (thanks Texas!)
When they've sprouted, plant them with the little legs facing down into the dirt and the new green shoots facing up. We don't plant them super deep, maybe 1/2 an inch, but if the temperature drops below 20' then we'll throw some plastic over them for good measure. Next spring, we'll be drooling over the results!!