weeds

amandstu

Sorry if I am being a bit technical but do weeds do more than just compete with plants for light and water?

The reason I wonder about this is that I have read in the past that this is the case with strawberries and scutch grass -I understand that there is a kind of chemical attack by the roots of the scutch grass on those of the strawberries.
And so now I wonder if this is the case with other weeds and plants.

I noticed that my fennel had been quiite badly set back when I got around to weeding it and so I wondered if there might be more to it than just something eating the roots or the ground drying out even though I was watering them quite conscientiously.

So do weeds commonly damage other plants via chemicals they release into the soil to inhibit rival plants' growth?

periodictable

Allelopathy is the phenomenon you are referring to. The classic case is exudates from walnut trees adversely affecting tomato or apple trees growing nearby. Simply chemical warfare between plants so as to ensure survival.

http://en.wikipedia.org/wiki/Allelopathy

http://gardening.about.com/od/gardenproblems/a/What-Is-Allelopathy.htm

amandstu

Does weeding aerate the soil around the plants to any degree?

Is it best to do it when the soil is not waterlogged if possible (so as to aerate better)?

My Potatoes

Weeding will do some aeration. Best to do your weeding early in the morning of a dry day. That way any weed remnants are likely to dry out and not propagate.

Weeds also harbour pests and diseases.