Rhubarb (Rheum officinale Baillon) is a very undemanding perennial vegetable, but often counted among the fruit species. This is due to its sour, fruity taste and the fact that it is mainly used for desserts. The harvest time begins in April; this month is also a good time to plant the vegetable in your garden.
The origin of the large leaved vegetable is Asia. It belongs to the class of the knotweed family (Polygonaceae) as well as sorrel (Rumex acetosa).
The eatable rhubarb stalk contains active ingredients such as potassium which is said to be dehydrating. A positive effect on the cardiovascular system should have ingredients like magnesium, iron, phosphorus and iodine. Tannins, glycosides, essential oils, apple and citric acids and also the intestinal friendly pectin are rumoured to have health-promoting effects as well.
You only can eat the stems of the rhubarb. Remove the leaves immediately and throw them on the compost. They contain the toxic oxalic acid which can summon renal failure or metabolic diseases. That is also why you should not harvest rhubarb after the 24th of June – after this date the proportion of oxalic acid is extremely high.
The vegetable is very carefree. However, the site should be well considered. The perennial plant cannot be replanted in its early years. The roots of the frost-resistant vegetable must settle down well. Rhubarb should not be harvest until its second year.
The ideal place for rhubarb is sunny to semi-shaded. The soil should be moist and water permeable. Due to the fact that rhubarb remains in the soil for a long time, the soil should be well prepared. Remove any weed, mix compost and organic fertilizer in the soil and dig it up well. Afterwards let the ground rest for two to three weeks.
Now it is time to insert your vegetable. The easiest way to do this is using root stocks which you get from garden specialist dealers, DIY stores or gardeners. Plant the rhizomes 2-5 cm deep and keep a distance of 70 to 100 cm. Seeds of rhubarb are not advisable because they are difficult to grow.
The vegetable can be harvested in the second year from April to June. When harvesting time has come, take a sharp knife and cut off the stems at ground level. In the first harvest year you should only cut off 3-4 stems at once. Thus the remaining stems can take in the energy of the plant. If you want to increase the harvest with the help of compost or organic fertilizer, please absolutely make sure not to harm the roots.
If the rhubarb has grown too big you can thin it out. Carefully dig out the plant and put it back in at another place where it has more space. You can also split the rhizome with the help of a clean and sharp knife or spade to get two plants. Before splitting just make sure that each half has at least one bud.