Chickweed - The problem is spreading...
Chickweed has adapted to survive in a number of different situations. They are a pain for gardeners, farmers and paddock owners alike who find it a resilient weed that does not easily give way.
Biology & Growth Habits:
Common Chickweed (Stellaria media) is characterised by a low growing habit and produces numerous flowers over a long period before distributing the seeds widely via birds, human traffic, ants (!) or animal waste.
Cooler temperatures are no barrier to growth with seed germination continuing down as low as 3 ℃. Prolonged high temperatures and direct sun causes Chickweed to wilt very quickly and on allotments solarisation (covering in plastic) may be a viable control method.
Plants can set seed all year round, producing between 1,300 - 3,000 seeds each and they remain viable buried in the soil for upto 25 years! Chickweed grows best in rich, frequently cultivated or turned soils such as allotments, compost heaps etc but it does not mind grassed areas such as paddocks.
The leaves are small and actually fold in at night time to protect against moisture loss and new growth so late evening spraying should be avoided.
Paddocks / Grassland:
Chickweed often indicates a rich or well fertilised field – preferring high potassium and high nitrogen levels that may also indicate low Phosphorous levels.
Mowing or topping cannot help and may even prompt growth by reducing tall, competitive shading plants and nitrogen-rich cut grass feeding the soil.
High in Oxalic acids it can build up nitrates that make it undigestible or potentially toxic to cattle & sheep – however it is attractive to many bird species.
Chickweed left to grow out of control can reduce hay or silage production by upto 25%
Treatment / Chickweed Control:
Continued spraying with a Mecoprop-P or Sulfonyurea product may cause some resistance issues in Chickweed.
Manual hoeing should be done only in dry conditions because a plant can re-root if left on wet soil. Be careful pulling up plants – even seeds not fully formed can still mature & germinate if left lying around.
Spraying can be done with a total herbicide or with a selective spray to avoid killing grass in paddocks, lawns, etc
Products to consider to control Common Chickweed are:
TOTAL weed killer:
SELECTIVE weed killer:
- The biology and non-chemical control of Common chickweed (Stellaria media L.) W Bond, G Davies, R Turner HDRA, Ryton Organic Gardens, Coventry, CV8, 3LG, UK