what would be cutting off my Mandeville blossoms right at the stem? They are being cut off after blooming. The hibiscus buds are cut off just before they are ready to open. Is this an insect or wildlife?
Your picture shows a white insect immediately below the unopened orange bloom but the camera is not close enough to identify it. Possibilities: aphids, scale or mealybugs. You can place one/few insect in a sealed, transparent, plastic bag and take it to your local garden center for identification.
Plants are turning yellow. I sprayed with all them oil and nothing stops though. They get water but not too much water. The plants are in direct sun all day long.
Check out the suggestions on this link: https://www.gardeningknowhow.com/ornamental/vines/mandevilla/yellow-leaves-on-mandevilla.htm
told it was a ficus but doesnt look like any pictures Ive seen
Looks like a Pink Mandevilla (Dipladenia). Can be planted outside in USDA zones 9-11 but will probably go dormant in z9 winters. Must be in pots otherwise especially during the winter months.
I would like put the Mandevilla plant in our garage, with natural light and non-freezing conditions, for the winter.
It would do better inside the home. Temperatures in the garage may be above freezing, but not warm enough. Here is more:
https://www.gardeningknowhow.com/ornamental/vines/mandevilla/winterizing-mandevillas.htm
Sure! Now would be a good time in your hemisphere.
Here are some articles that will help you with their care: https://www.gardeningknowhow.com/ornamental/vines/mandevilla
I brought this mandevilla pot inside the house just before the fist frost. I trimmed the entire plant and placed by the patio door that's sunny. It's been growing quite well. Now vines are looking for the place to crawl. What should I help them?
I suggest getting a small trellis to add to the container or even just behind it. Here are more ideas:
https://www.gardeningknowhow.com/houseplants/hpgen/vining-plants-for-inside-the-home.htm
Being a subtropical plant, this week in central Georgia the temps are going down to 32 degrees at night. I have already planted my two. Covering them with a bed sheet will be ok?
Yes. Cloth is preferred over plastic, unless cloth is under the plastic. Here is more about unexpected frosts:
https://www.gardeningknowhow.com/plant-problems/environmental/frost-how-to-protect-your-plants.htm