(Editor's Note: This article was originally published on March 12, 2008. Your comments are welcome, but please be aware that authors of previously published articles may not be able to respond to your questions.)
Surprisingly, many people treat the miniature roses (often sold as holiday novelty plants) as a throwaway plant. Not true!! Although not recommended as a houseplant, they are sold as such. Outdoor light and humidity conditions are hard to replicate indoors, especially in the winter when heated houses are, as a rule, very dry. Don't throw the poor things away though. With a minimal amount of care these little beauties can be a wonderful addition to any garden. I discovered this fact by accident. They were on sale at my local box store and I could not resist buying a handful. I kept them alive--barely--on a windowsill and come spring, not knowing what else to do, I stuck them in the ground just to see what would happen. Lo and behold, they flourished. When fall arrived, I decided to leave them out of curiosity. I dumped a shovel full of soil over them while I was winterizing my other roses. The next spring, there they were, alive and happy, new shoots sprouting all over. This is in my zone 5a garden!!
Mini roses are true roses; the main difference being that they have been bred to stay small in size. They have smaller flowers than regular roses, but this works well because they are smaller in size, usually between 12 and 24 inches tall. They come in a variety of colours just like the bigger roses. Despite their tiny size, they are hardier than most tea roses. I have found that if deadheaded they are also repeat bloomers. They are, of course, succeptible to the same pests and diseases as other, larger types of roses.
Planting. Your newly acquired mini rose is planted the same as larger varieties. Pick a spot that gets at least several hours of sunlight. Dig a hole larger than the pot it came in. Add some good compost to the soil and stir. Gently remove your mini rose from its pot and ruffle the roots a little bit. Place your rose in the centre of the hole with the roots spread out as much as possible. Fill in the hole and firm gently. I like to leave a little depression, kind of like a moat, for the first watering, then fill the rest of the way after it has soaked in.
Most mini roses are not grafted so there is no need to worry about covering the graft or suckering.
Fertilize the same as you would your regular roses. These little guys bloom all season so therefore can be heavy feeders. Give them a shot in the spring when they first develop leaves, then after each flush of blooms. Stop fertilizing roughly six weeks before first frost. The more you fertilize, the lighter the strength you need to use. In my zone, they get the spring fertilizer and then again mid-summer, if I remember.
Watering is essential for all roses. The minis do not have deep root systems, so this is even more important. Mine get a drink at least once a week if it hasn't rained. I make the little moat around them and fill it with water, let it soak in and then repeat. This guarantees that the water goes where I want it instead of running off. When it has soaked in, I backfill over the damp soil to prevent loss due to evaporation. (This is a trick my grandfather taught me when I was six years old and I have always done it. I make the same moat around all of my newly planted seedlings as well). Always avoid getting the water on the foliage of your roses, especially in humid weather, as this can cause fungal diseases.
Pruning. These little plants are the easiest to prune. I wait until new growth shows in the spring and then cut back any dead branches. I do not prune them heavily, they are small and compact enough as it is. Again, dead heading any spent blooms helps to maintain the overall appearance of the plant.
Mini roses, just like regular roses, come in all shapes. There are climbers, trailers, microminiatures (6 to 12 inches tall). There are also the newer Mini-flora roses, which have a larger bloom size and are a bigger plant than the minis. Those I have bought in the box stores are the microminiatures and in my garden they rarely exceed 12 inches.
They are wonderful in a hanging basket, planted with sweet alyssum or annual lobelia, something low and trailing. They make nice focal plants in a container too. Consider mini roses planted in a strawberry pot! In colder climates, though, I would recommend planting them in the ground to overwinter.They make excellent border plants. I keep all of mine in a bed by the front door; it's a "mini" rose garden.
This year, after the madness of Valentine's Day, and the poor little mini roses are setting neglected on the shelves, plastered with "reduced" stickers, dying of thirst, consider rescuing a few. Imagine a mini rose garden of your very own, full of tiny wonders, for less than the cost of one standard type rose.
Many thanks to grampapa, heidi2005 and kennedyh for their wonderful photos.