Despite the long cultivation period, rhubarb is rarely afflicted by diseases. Rhubarb mosaic disease in particular poses a serious threat. Diagnosis and possible treatment are explained in the following lines.

Assign the symptoms correctly

There are usually several viruses that trigger a mosaic disease in rhubarb. The toxic oxalic acid content in the leaves does not bother the pathogens much. The symptoms are differentiated accordingly:

  • in spring countless spots in light or dark green shades on the leaves
  • brown spots along the leaf margins
  • yellowish, mosaic-like discolouration
  • round, light brown necroses with slight convexities

Viruses are introduced in a variety of ways. Young plants obtained by division by fellow hobby gardeners often contain the long-lived viruses. Aphids and other sucking pests are also considered vectors. A direct control is not yet known.

Indirect control promises success

If the described symptoms of a rhubarb mosaic disease come to light, the only thing that will help is immediate clearing. To prevent this from happening in the first place, the virus should be prevented from being transmitted. Experts recommend taking the following actions:

  • Do not plant rhubarb in the eaves under fruit trees
  • Check daily for aphids and fight immediately if infested
  • Only use certified seedlings that have been tested for virus-free

If the rhubarb mosaic disease spreads in your garden anyway, remove all affected plants from the bed. The cultivation break is then extended from 5 to 7 years before you can plant rhubarb there again.

Leaf spots rarely limit harvest

The frequently occurring leaf spot disease (Ascochyta rhei) resembles the mosaic disease at the beginning. The spots on the leaves have a brown center surrounded by a red or yellow border. As the process progresses, the brown dots fall out of the leaf tissue.

If the affected leaves are cut out in time, the stems can still be harvested. On the other hand, if you fail to clean the rhubarb from the diseased parts, you risk the complete death of the plant.

tips and tricks

Infection by fungal spores or viruses is an ever-present danger in the hobby garden. As a comprehensive tonic for the prevention of diseases of all kinds, liverwort extract is making a name for itself. Sprayed regularly on rhubarb from a young age, pathogens do not even settle. Even voracious snails avoid the plants.

GTH

Category:

Vegetable garden