"Protecting tender new growth?"

Sorry for the major typo. I'm on the backside of a migraine and obviously not as sharp as I thought I was, and now I can't figure out how to edit a headline...

You could use a cloche (bell jar) at night and remove it each morning. Since the plants are tiny, you could cut the bottom out of a couple of two liter soda bottles to make cloches. I wouldn't pile a lot of mulch around them because that would stay too wet in spring & possibly lead to rot. Good luck!

I would put a couple handfuls of oak leaves on them if the temps are supposed to go down below freezing. Just keep a pile of leaves available near the roses or, if the leaves are very dry, in a bag nearby so you can add them if the temps fluctuate too much, especially if they go down into the 20s. I don't think you need to worry about it more than for the next couple weeks and you may not have any temps dipping that low coming up at all.

Kate

Cardboard shipping boxes slipped upside down in place & weighted or pinned to keep them there are easy & insulating. Keep a folded down pile of them for just this use, both for the open garden & pots. Saved tender foliage of many plants over the years this way, placing the boxes before the temps are expected to dip & removing them when they rise. If precipitation is coming with the cold, just slip a trash bag over the box.

Potted up last Summer's baby bands & lined them up in an old fiberglass window box set on the front porch out of the weather but not the cold last December. Whisked out a big cardboard box that covered the whole row every time the temps fell below 12 degrees. They actually grew 6" over the Winter with that ocassional protection.

Any of these suggestions are good but you have to be very careful to remove covers during the day so they don't over heat inside and fry. Particularly with the bell jars or pop bottles because they will magnify the sun. At least with the cardboard if you forget it will be in shade not sun.

Everything above will either be complicated or will lead to rot on hot days.

What I do is mound chickweed around the new growth. Chickweed has a high water content, continues (for a while) to live after it's been pulled up by the roots, won't add to any propensity to rot, can by grown through by new rose growth, is free (and most of us have it readily available at this time of the year.)

It won't be blown off by spring winds (boxes), it won't magnify the strength of the sun.

It's easy and will eventually (about May) die on its own and become compost.