How to recognise it
Growth stops unexpectedly, eg bulbs fail to flower or brassicas fail to form a head.
What causes it
The lack of growth is caused by the absence of, or a malfunction within, the growing point (the ‘apical meristem‘). This may be caused by a number of different environmental, pest or pathogenic reasons, including:
- Damage from a pest or disease.
- Nutrient deficiency.*
- Periods of low temperatures (particularly affects brassicas).
- Exposure of bulbs to high temperatures after lifting or during storage.
- Planting bulbs at the wrong depth.
- Transplantation shock (may occur with bulbs planted ‘in the green‘).
*With bulbs this may be caused by planting too closely or by the foliage being removed too early the previous season so the bulb cannot build up its nutrient reserve.
Why it’s a problem
Failure to flower or, in the case of vegetable crops, to form a head, can ruin a display or harvest. Blindness may also be an indicator of a more serious underlying pest or disease attack.
Where you are likely to find it
Brassicas, particularly broccoli and cauliflowers, and bulbous plants such as tulips and narcissi (daffodils).
How to prevent it
Ensure that plants are correctly cared for, both in terms of their planting (depth and spacing) and their feeding/watering regimes. Check regularly for pests and diseases and take appropriate action to prevent or get rid of them.
How to get rid of it
Once blindness has set in it is impossible to reverse the process. You should identify the cause of the blindness and take steps to prevent it happening again the following season.
Bulbs which have grown ‘blind’ should flower the following year so long as the underlying cause has been recitified.
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