RHUBARB.

(Rheum rhaponticum).– This crop is usually grown in the vegetable garden and can occupy any odd corner. This does not mean that it does not require good soil, but that as the plants remain year after year without moving, they are best grown in some part of the plot away from the ordinary annual vegetable crops.
The best time to plant is in February or March, but the soil should be prepared the previous autumn, being trenched to about 1 yd. deep, and given a thorough dressing with farmyard manure, worked in from 1-2 ft. below the surface. Single crowns are planted 4 ft. apart each way. They are just covered with soil and then mulched with horse droppings. When active growth has begun the manure should be forked in. No stems should be pulled until the second season after planting, but from then onwards the stems can be gathered early in the season each year. It is a mistake to gather rhubarb too late into the season, as it weakens the plants and makes them useless for subsequent years.
Rhubarb forces easily for early spring use. Two methods are available. One is to lift the crowns in December or January and pack them into boxes of moist soil, which can stand under the greenhouse shelves, or in any frost-proof shed. The soil is kept just moist, and the stems which grow, though they are thinner and earlier than the main crop stems, are more delicate in flavour and very often preferred to outdoor-grown rhubarb.
The other method is to invert over the plants wooden boxes, tubs or other coverings, and at the same time to pile over the crowns and round the edges of the boxes some old, decayed manure. It is best to remove the manure or fork it in as soon as the weather is warmer, otherwise the plants tend to become weak. Rhubarb crowns that have been lifted for forcing are no further use another season, but plants that have remained in the open, and been forced a little by the inversion of boxes over them, will recover their hardiness and be satisfactory in succeeding years.
Propagation.– Rhubarb is increased as a rule by division of the crowns. Each separate crown should be pulled off and replanted in spring. Increase by seeds is also possible, though seedlings vary in quality and must be selected judiciously if good rhubarb crowns are to be obtained. The seeds are sown in drills in April, and the seedlings planted out in permanent beds the spring following.