Bird, I hope all went well and wish her a full and speedy recovery.
We had very light snow in various places around here like near Lexington where the mentioned garden is (was?) Temps were predicted for high 20's last night but we only got down to mid 30's at our place. One outside thermometer claimed 34.x and the other 37.x (opposite sides of the house and so on side shielded from the wind some heating from the brick wall interferes a bit.
If I recall correctly, you can get frost with air temps up to about 37F with clear skies supporting radiative cooling and no wind to provide a flow of "warm" air.
Regarding mulch, weed barriers and such: I prefer news paper over plastic mulch as it biodegrades. Sawdust and wood chips are OK but you need to compensate for their nitrogen requirements to avoid depleting the soil. I have been thinking of trying shredded paper from our efforts of enforcing personal privacy and security.
There is no such thing as long term weed free gardening. The best I ever did was in San Diego where I landscaped our front yard. I covered most of it with heavy black plastic with soaker hoses under it on a grid. I topped the plastic with a couple inches of crushed volcanic rock. Specimen plantings were accomplished by sliting the plasctic and inserting a plant (mostly various cacti but some others like Sago Palm etc.) I watered about 3-4 times a year by turning on the water to the soaker hoses. Most rain water ran off. Eventually blowing dust etc will give a weed seed a chance to sprout and take hold but with little dirt for the roots they are super easy to pull up.
I have tried geotextile as a water permeable weed barrier in gardening but the weave was too course and grass and weeds went right through. Looked terrific for a week or so before failure was obvious. There is some Tyvec geotextile used in leach field applications and such that would probably work a lot better but I haven't personally tried it.
Pat [img]/forums/images/icons/smile.gif[/img] [img]/forums/images/icons/smile.gif[/img]