If you are still following this forum, we are only UK in origin. We have a lot of followers from around the world though many don't say where they are based, which is important in gardening.
Even as a chemist, it's not an easy question to answer. I would go along with Jenny's answer, but I don't know how the chemicals might interact. If the intention is to hit both the Crab Grass and the Poa Annua, I would hit them separately. Possibly with a short delay inbetween.
I think in leaving the European Union, we have left the real Nanny State. But things take time to change.
location: Surrey Hills, England, ex-woodland acidic sand. "Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
Just want to point out that I wasn't supporting the use of the weedkillers, but pointing out that the advice received from the university seemed a bit odd, everything doubled to give twice as much of the same concentration.
Doncaster, South Yorkshire. Soil type: sandy, well-drained
@dm2244 there are currently no chemicals available to kill Poa Annua in your lawn without killing the entire lawn. The only way to remove it is by hand using 2 eating forks, it comes out quite easily, and regular scarifying or verticutting. You also need to make sure you cut the seed heads off before they seed. Poa Annua works on a two week cycle. So before mowing rake your lawn, to make sure the seed heads are standing proud and then mow.
I checked, and Crab Grass like Annual Meadow Grass is also an annual weed. The only cure is a combination of: constant hand weeding, which could be manual or spot chemical; ensuring it doesn't seed (one year's seed is seven year's weed); keeping the wanted grass growing healthily; and regular mowing but not too short.
For the spot chemical, I use Malt Vinegar (±5% acetic acid).
I practice a similar strategy with Hairy Bitter Cress. The compensation, this is edible.
location: Surrey Hills, England, ex-woodland acidic sand. "Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
I have never used a chemical weedkiller - ever. It occurs to me that if you are having extreme difficulty growing lawn grass perhaps a lawn is not appropriate to your environment. Consider what grows well in your climate and soil and grow that. Forget trying to reproduce the green desert lawns that grow so we'll in nanny states.
Posts
Ignore button is the best solution here methinks.
I live in west central Scotland - not where that photo is...
Even as a chemist, it's not an easy question to answer. I would go along with Jenny's answer, but I don't know how the chemicals might interact. If the intention is to hit both the Crab Grass and the Poa Annua, I would hit them separately. Possibly with a short delay inbetween.
I think in leaving the European Union, we have left the real Nanny State. But things take time to change.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
Our “environmental nonsense” suits me just fine. Is what she is really saying
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
I do however, admit to the occasional use of weed killers.
When you don't even know who's in the team
S.Yorkshire/Derbyshire border
For the spot chemical, I use Malt Vinegar (±5% acetic acid).
I practice a similar strategy with Hairy Bitter Cress. The compensation, this is edible.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
It occurs to me that if you are having extreme difficulty growing lawn grass perhaps a lawn is not appropriate to your environment. Consider what grows well in your climate and soil and grow that. Forget trying to reproduce the green desert lawns that grow so we'll in nanny states.