Is there any way to move them inside next to a south or west facing window? The older and bigger they get the more hardy they will be. In any event if you have not planted them in the ground yet there is no way you should try to do so now. They would not get any time really to root in the ground.

They've been in-ground since June.

I would leave them in then. I think removing them wouls casue too much root damage for them to recover.

Have you considered building a small structure over them to protect them in their current location. With both plants still quite small, you could use a few stakes/canes to create a tee pee like frame over them, then just wrap some clear polythene around the frame. You could improve that further by adding a heat source inside the frame, but I would have thought the frame and cover would be sufficient.

Here is a link that might be useful: Palm Trees, Small Palms, Cycads, Bromeliads, Tropical Plants

If you are concerned about an established palm in a zone not totally appropriate, consider this palm, growing just below street level, in the ground, in Edinburgh, Scotland.

{{gwi:954890}}

Edinburgh is actually zone 8a, although it doesn't get high summer temps at all so trachies are pretty much all that can grow there

Eric, my 3 gallon size needle palm survived a zone six Massachusetts winter this year.I used the leaved filled enclosure, sprayed a couple of times with wilt pruf and fungicide and used a trash can cover on very cold nights and cold rainy days.I think the key is to keep it dry.I did plant mine in early may of '06,not in june.

I would leave them in the ground with the leaf cage enclosure, but fill with straw or hay instead, and then cover each structure with a light colored tarp to allow light and airflow in, and keep water out. If you're really worried about losing them, use some christmas lights in the middle of the mulch pile with a thermometer, just to make sure it doesn't get too cold, especially with the Trachy.