Rhubarb is an undemanding perennial vegetable that is often mistaken for a fruit, probably because it is mainly used in desserts. Originally from Asia, it belongs to the class of the knotweed family (Polygonaceae) as well as sorrel (Rumex acetosa).
The edible rhubarb stalk contains healthy active ingredients and is the only part of the plant that should be eaten. Remove the leaves immediately and throw them on the compost, they contain the toxic oxalic acid that can cause damage to your body.
The quality of a rhubarb plant’s leaf stalks decreases considerably in proportion to the time the plant spends at its location. It therefore makes sense to dig up a rhubarb plant approximately every five to seven years, split it and then replant it.
You can carry out this work in autumn, from the end of March to the middle of April or alternatively in late August to early September, as soon as the soil is free of frost. To start, water the plant that you would like to split a day or two beforehand with ten litres of water per square metre. Prick with a spade at a distance of approximately a hand’s width around the plant and loosen the roots and lift the plant out of the plant hole.
You can then split it by cutting into it with a spade so that one or two buds remain on every fist-sized piece. When splitting in autumn, these are easy to find because there is one at the base of each stalk. In spring, the buds are hidden under dark bud scales and can only be seen more clearly when they swell.
Loosen the soil at the new locations, add a 10 litre bucket full of compost and plant the pieces of cut up rootstock deep enough so that the buds are level with the surface of the soil or protrude slightly. Make sure to finish off with a good watering session.
Tip: Always have a mixture of sufficiently younger and older rhubarb plants in the garden, as freshly split and newly planted seedlings usually need two years before they return to full yield.
