Rhubarb is one of the crops that is easy to grow because it almost looks after itself. If you have an established clump then forcing tender young stems is very easy. There are many methods of forcing rhubarb but you need one of excluding light. Use special jars for forcing rhubarb or any other container like an old tea chest, a bucket or barrel or a plastic dustbin, or just make a frame from wire-netting and canes and pile straw into it, pressing it down firmly.
For really early crops, lift a well-established root and leave it on the surface for a few weeks to make it believe that winter is more advanced than it really is, then replant the crown for outdoor forcing or bring it into the greenhouse. If you have a warm greenhouse, place the rhubarb crown under a bench screened with black plastic. If your greenhouse is not warm then you can choose to pot up your rhubarb crown, put it in a plastic bag and take it indoors. Make sure that in the plastic bag is enough air by making few small air holes in it. Place the bag in a warm place, under the stairs or in a kitchen cupboard, and check it from time to time.
Forced and blanched new shoots produced from chicory roots are an enjoyable winter vegetable. Grow your own roots from plants sown in late spring or early summer. Outdoors leave the chicory roots in situ, cutting the foliage off in late autumn. Heap soil over the stumps, creating a ridge of about 20 cm high. Place cloches over the top and insulate on cold nights but removing the insulation during mild, sunny days to allow the sun to warm up the soil through the cloches. Check the roots in late winter to see if they are ready to be cut.
You can also try a faster method by lifting the roots from the ground from mid autumn onwards and live them on the soil surface for few days. This will help to retard growth. Trim the tops to leave 2.5-5 cm stump of growth. Pot them up or store them in a box of sand, peat or dry soil for later use. Three weeks before you may think you will want to eat some, pot up 3 roots in a small pot and cover the pot with a second pot with the drainage holes blocked. Keep the pot at abut 10-18 Celsius degrees (50-65 F) and keep the compost just moist. The forced chicory should be ready to harvest in about three weeks.