This does not keep redwood roots out. They go around the sides and in my compost pile right through it. Concrete doesn't work either as we tried that with one raised bed. The only thing that works is a large gap of air between the bottom of your bed and the soil. My husband was not willing to start over to do that after I had created a number of beds so most of mine still require pulling the pots out to check. If I can't easily pull out the pot, I can be sure that the redwoods have gotten into the pot. Since I can't attach photos to the list anymore I have added an early photo of one of my first raised beds to my wiki contributor's page. I added wood chips to the top so the pots and the gravel/sand aren't so noticeable and also because when I first started we were having significant rainfall and the wood chips soaked up some of it. I put tags under the first pot as well in case the birds pull out the tags in the upper pots. And I also added a photo for this discussion of a nest of roots I removed from either a 10 or 11 inch deep pot. You can see there wouldn't be room for much else. I'll remove that photo later. https://pacificbulbsociety.org/pbswiki/index.php/… Mary Sue On 8/29/2022 10:49 AM, Jane McGary via pbs wrote: > To exclude invasive roots, I lined my raised beds with heavy-duty > woven groundcloth (the kind used in nurseries, not what they sell in > garden centers). Water passes through it. Like redwoods, the Pacific > native "red cedar" (Thuja plicata, not a cedar, nor what they call > "cedar" in the east) has endless moisture-seeking roots. Such trees > can be helpful with a bulb collection in that they reduce summer > moisture. > _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/… Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net> PBS Forum https://…