Q. Dear Peter, over the last couple of years, some sort of moss has invaded my garden, especially my strawberry patch. It looks like Spanish moss but I am not sure. I have tried spot treatment with Roundup and other moss killers, but it keeps growing back. Is there anything I can use to wipe it out once and for all that won’t hurt my produce? Kevin S. Henson – Tacoma, WA
A. Well I can say with certainty that it is not Spanish Moss, which by the way is not a true moss but is actually an air plant in the Bromeliad family – a vascular epiphytic flowering plant. So as you can see determining what type of plant you have can be confusing. The only plants I am aware of that resemble Spanish Moss are native lichen that can be found hanging from trees like Garry Oaks and not usually found invading a strawberry bed. If what you have is a true moss products like RoundUp (active ingredient glyphosate) will not work since mosses don’t have true root systems. If you are using other products labeled for moss and they are working but the problem reoccurs then you will need to change the environmental conditions. There is no chemical that will “wipe it out” permanently since there are moss spores floating around and ready to reinvade any suitable area. When the intention is to grow a moss garden there are three conditions that are provided: acidic soil, compacted soil (rollers are used to compress the soil) and lots of moisture. So it makes sense that if you want to discourage moss in your garden reverse any and all of the three conditions that currently exist. Bring your soil’s pH closer to neutral (for strawberries pH of 6.5 would work well). Work in organic matter to loosen the soil and allow for better drainage – especially if you have clay soil. If you find there is some standing water you may need to consider installing some sort of drainage tiles to move water away from the beds. It is also helpful to improve air circulation by limbing up a tree or moving a fence or other obstruction.