Permeable means it s ability to allow liquids to pass through. Chicken wire is fine if you have moles/voles but landscape fabric is only mildly permeable. Testing consistently shows it slows drainage substantially. It is not ever recommended for the bottom of a bed by experienced gardeners and it would have no effect on the moles and voles anyway. 75:25 compost:loam is high on the compost side and the quality depends on your definition of "loam". Means many different things. But as long as it isn't so-called "top soil" or sand a 50/50 mixture of it would probably work. More commonly you see the recommendation for 40:60. But you will have to add more compost at least once a year and better 2x a year as it continues to shrink as it decomposes. I get the impression you aren't interested in first trying to improve your native soil and incorporate it into the bed, correct? That is the best route to go. But if not then you need to understand that overtime it can affect whatever you fill your bed with unless you made some sort of solid bottom box which is not at all recommended. But you can still make it work with a framed raised bed on top of it with chicken wire or hardware cloth on the bottom IF you keep the bed well and frequently amended with quality compost. Over time the leachate and soil bacteria will improve the soil below the bed as well. Dave

dizadner ... your reaction to emergence of grass -DANG - is the universal gardener's language. LOL ... if that 'grass' spreads by runners, getting rid of it [even with herbacides] will be a long-term effort. No magic bullets. Re: landscaping with rocks. I have terraced the very steep slope in my back yard with stone walls. And over the years have tamed the clay soil with applications of organic matter. If you are planning a perennial bed, you might want to "cover crop"[grow/cut/dig in] for several years and then plant your permanent shrubs/trees. FWIW, The difference in size/productivity between trees planted before/after that kind of prep is dramatic in my yard.

Beautiful garden. I think it will be difficult to keep grass looking good around raised beds unless you have a lawn mowing company and then it will not be a problem. As' localeater' mentioned I would not use pea gravel. Seeing your beautiful garden I would not use any kind of gravel, but I think a stone path between the two beds and from the patio would look good. Of course if later you decide that that is not the place for your beds then it would look silly to have a path from the patio to the middle of your lawn. Good luck on your garden.

To follow up with the other comments - it sounds like you have a soil amendment on top of your actual soil. I would suggest dig down with a spade into the actual soil and turn that over and blend it in to the MG amendment. The combination of the two should be better than leaving them one on top of the other. Once they are blended, that is the mixture that you want to test. If you are not going to test, it is a rule of thumb that heavy feeding annuals like vegetables pull nutrients out of the soil that must be replaced in some way every year. If you are doing organic gardening, look for a complete organic fertilzer like Espoma Garden-tone or Dr Earth Tomato Vegetable fertilizer. Apply that in the early spring because the organic ingredients need to be broken down in the soil before the NPK is available to plants in May and June.