For all my potted roses I use Fafard 52 mix.
IT seems to have the right size materials but needs to be watered more offen.

Stan C

We grow c. 60 roses in pots.

I would not reccomdend using only compost or potting mix for roses, as it will not drain properly.
I use a combination of 1/3rd to 1/2 native garden soil-to 2/3 to 1/2 compost or potting soil.
to this I add amendments if they are not included in the potting soil.
for every 3 gallons of pot space,amendments include
- well rotted manure, the bagged stuff works well for my roses. c. 1 cup or so, for 3 gallons of pot space, mixed in very well to the potting mix.
-a cup of alfalfa, some bone mean,some blood meal, and earthworm castings.
I stopped using mushroom compost after reading a Hortico catalog which suggested that it can harm rosebushes.
I also mulch the pots in autumn with 1/2 well rotted manure and 1/2 composted plant material.

Luxrosa

We have about 75 OGRs in 5 gallon pots waiting (still) for the new garden beds. My husband blends his own potting mix with a good top soil we buy locally, adds composted manure (mixed with rotted hay from our horses), pine bark mulch, vermiculite and perlite. May be overkill but the roses have done extremely well and some have been in their pots for 4-5 years, still waiting for homes. The mix is lite but holds moisture well. We do feed with time release fertilizer in season and top dress the pots with mulch to inhibit weed growth from the compost...works great for us.

Hmm, I just use a commercial organic potting soil that I buy at the nursery. Our local soil is pure clay, not suitable for pots at all, even blended I would guess. Are those of you blending your own working with a sandy or sandy loam soil? In any case, you folks are working way harder than I am!

Rosefolly

Yep, a commercial organic potting mix for my container roses too, Rosefolly.

Randy

I usually mix coir into a commercial potting mix, because the coir makes the very top of the soil less prone to drying into an almost cardboard-like substance. I don't like to water the plants and have most of it overflow to the side, down the space between the pot and soil, and instantly go out the bottom because the surface won't allow water to penetrate if dry. Of course, perhaps I shouldn't let the soil get so dry in the first place. I have taken to mixing in several generous pinches of worm castings. I also add some perlite with the coir. This has worked very well for me after trying innumerable combinations of ingredients.

However, I don't usually keep roses in pots for more than 2 years, at least on purpose.

Starbucks coffee grounds

Luxrosa, did "Hortico" say why they believe that Mushroom Compost will harm roses? We humans eat all those mushrooms, so I assume it's not because of any chemicals used in growing the mushrooms. I find the statement very interesting and I'm now very curious to know why!!! If anyone has an answer, I would surely appreciate knowing why.

I've used mushroom compost with in ground roses routinely; and to a lesser extent with potted roses. In my experience, it does not 'harm' roses, but i have sometimes found that the bulk stuff is not as aged as you would like it, meaning it can burn the plants if applied directly to them. You can tell, easily, when the MC is not aged enough. When it is too fresh, you have to spread it out on your driveway (or wherever it has been dumped) and rake it around some to expose it for a while. And cope with the smell a bit. For this reason among others, it is always good to share rose blossoms with your next door neighbors.

The other thing to watch out for with MC is that it will push your soil pH to the sweet side. If you are in sweet to neutral soil to begin with, this can be a problem for your plants. Solution is to mix the MC with some acidic matter like pine fines or coffee grounds.

For roses growing in pots, the MC can be rather dense and can inhibit drainage. Again, fix is easy--mix with pine fines.

Luxrosa and Kaye, thank you for sharing your potting mix recipes. I am going to try both this Spring. Some roses are just terrific in pots, and it is great to have a few plants in pots to move around your patio, yard, deck and so on. So, having a proven potting mix recipe is important. I appreciate the suggestions.

I'll second the vote for the Fafard mix which I've used for years. Miraclo Gro and Schultz also OK. I have about 40 potted roses in various sizes - now all of them are in the house for the winter.
Went to my local garden center for a small bag of the mix to use inside and picked out a 16 quart bag of Fafard with a sign that said $5.60. It rang up at $2. and I protested but two check-out clerks verified the computer and insisted they were right so I stopped arguing. Will have to get more next time if that's the way they feel about it!