2. Failure to control temperatures inside the rooting area. Be sure the plastic is shaded if it might be in full sunshine at any time of the day. It will heat up quickly if sunlight passes through the plastic. Aluminum foil works well but you could also slide a plastic cup down over the area.
3. Failure to do the rooting at the right time of year. Trees differ greatly in the best time to air layer. Spring is usually the best time, but early autumn is another good time to try.
4. Failure to try different equipment. Look online for air rooting balls and air rooting cups. One DIY method is to use a small resealable plastic container and lid, with notches carved on opposite sides, to allow the rooting limb through.
Those are a lot of things to try. Let me know what works.
Q: Should I protect my potted yucca for winter? Charlyn Elliott, Suwanee
A: Assuming you have a common Yucca filamentosa, you don’t need to do anything special. It is usually winter-hardy but you can wrap the pot with insulation if it gets really cold. Water it occasionally so the roots don’t dry out.
Email Walter at firstname.lastname@example.org. Listen to his occasional garden comments on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, www.walterreeves.com, or join his Facebook page at bit.ly/georgiagardener for his latest tips.