We don't know your zone, so the answer will be general. Yes, they actually want to be outside like other roses. Roses want a minimum of 6 hours of sunlight, more if possible. Gradually introduce your new roses to the outdoors by putting them outside in a sheltered spot, and giving them a little direct sunlight a day, increasing the time, until they can stand being out in full sun. If the leaves look like they are burning, reduce the time.

Many roses will lost some or all of their leaves when transplanted. make sure to keep the soil moist (not too wet, not dry at all), and they should recover quickly. Do not fertilize until you see new growth, usually new leaves.

Can miniture roses survive the winters of zone 3a?

I have just written this for our local RS.
NOTE : The text may be edited and shortened a bit and it's not final. It will be on my web-site after it's edited.

Tips for planting and growing Miniature Roses

# 1 : When buying NEW minis, which come out of the greenhouse. "Do not" expose them to direct sunlight right away as you may burn the foliage.
Keep in the shade for at least a week and then gradually give them 2 to 3 hrs of sun a day for a week to 10 days. Then you can put them in "FULL" sun.

# 2 : Planting. (Canada and northern States)
When you buy a new mini in a 3 to 4 inch pot, do not plant them into the ground right away !!! If those small pots are full of new roots, I cut appr. 1/4 inch off the bottom of the root ball with a steak knife. This way new fine hair roots will develop really fast.

I first transplant mine into one gallon pots. After 3 to 4 months the one gall. pot may have roots right down to the bottom. If roots go around in circles itÂs time to plant into 2 gall. pots. Again, I cut about 1/2 inch off the bottom with a large steak knife. From the 1 gall. one could plant them into the ground, but I prefer to leave them in the 2 gallon pots for the first season.

Years ago I did some experiments with my own minis and those I grew on in pots were 2 to 3 times larger after one season compared to those which were planted right into the ground.
Up north the ground never warms up until late May compared to the pots where the soil warms up fast with just a few hrs. of sun a day.
In the southern & hot US states it will be OK to plant right into the ground, but after you had them in the shade for a week to 10 days.

# 3 : Fertilizing. "DO NOT" use chemical fertilizer for potted roses !!!
My friend and I have both killed a number of minis in one and two gallon pots, using the fertilizer we use in the rose beds. Too much nitrogen will damage or kill the roots and the plants may die.
Use slow release Osmocote or even better, use the organic mix which a friend and I have been making for years. You can not over fertilize (kill the roots) with our organic mix.
We have been using this organic mix for the last 6 to 7 years with outstanding results. The foliage, health and vigour of our minis in pots is exceptional as our rose show results prove.
Water soluble fertilizer can also be used. If it calls for a teaspoon for 4 liters or 1 gall. of water use a level spoon, but "NEVER" a heaped one. As this is also a chemical, use a bit less as too much may damage the roots but may not kill the plant. Again I am speaking of my own experience.

# 4 : Needless to say, water, water, water !!!
Never lets your pots dry out as they have to watered more often than roses in the ground.

Here is a link that might be useful: Roses of Excellence

Basically, the link is a repeat of this article.

This is an old post but I'm sure many people still have this question. I transplanted mine from pots into the ground with compost added to the soil in a spot that gets a good mix of sun and shade and they did great!