Steve812 said: I don't have much need of zone 4 cold hardiness in roses, but I'm thinking maybe Joanne might. I think you will find that a number of the rugosa-acicularis hybrids developed in Canada are rated at HMF to zone 2b. William Baffin, for example. I did not check my recommendations against HMF hardiness listings, though.

There is only so much room in my city garden! I have approximately 80 different roses. I have most of the Explorer & Parkland series. Haven't bought any of the New Canadian Artist series, but "Campfire" is on my wish list.

What I would like to do though, is plant more roses at our farm. Problem there is that it gets colder than -40 in the winter. Zone 2, possibly Zone 1A. Also, we only go the the farm once a month, so the plants are totally reliant on Mother Nature for water

The Explorer and Buck roses are some of my best roses every spring, and I know why. While we may not have the extreme cold, we do have extreme variations throughout winter. The hybrid teas fall for the brief warmups and bit by bit, with each zap of cold, their stems die back. When spring really does get here for good, the HT's have blackened stems where the zone 3 roses do not. The zone 3 roses are ready to go in April, where the HT's have wasted all their energy and now are struggling to leaf out on their 2" damaged stems. They start out weak and look bad all season. My John Davis is blooming like crazy now. It is not only cold hardy, but heat-hardy also. It really should be on the list for EarthKind evaluation.
In the past, I bought all sorts of plants that challenged the hardiness zone. Now, I play it safe, because I got tired of the marginally hardy plants looking scraggly all year.

I think I need to add John Davis to my list of roses to seek for fall planting.

The List - Try #1

Light - Your rose should get at least six hours of direct, unfiltered light. Some hybrid teas need more than eight to bloom. A few old roses and hybrid musks might get by on just a bit less.
Water - Soil at six inches and deeper (established roses) should not dry out. Some well-established plants do fine through long dry spells; but repeating roses that fail to bloom in summer or fall might sometimes be reacting to stress from drought. Give them a deep, slow watering.
Standard Nutrition - Fertilize with an organic fertilizer such as Mills Magic. Or use a slow-release fertilizer like Osmocote. Too much nitrogen will cause growth at the expense of bloom.
Non-Standard Nutrition - Have your soil checked, and have it amended to fix imbalances. Sometimes Epsom salts or bone meal are used to encourage bloom.
Bud Union - If it's a grafted rose, check the bud union. Sometimes a graft is bad or the scion dies and the rootstock pushes up: and sometimes rootstock doesn't bloom very well.
Pruning - Pruning the wrong way can have a negative effect on blooming. Prune once-blooming roses within a few weeks of when they have bloomed. Bloom repeat-flowering roses such as floribundas and hybrid tea roses in spring before they start to leaf out. If you live in a place with a lot of freezing and thawing in spring, you may want to delay doing this until hard frosts have passed - especially with frost-tender plants.
Frost - Late frosts can kill rose plants. Or they can freeze spring rose buds. By planting cold hardy roses this effect can sometimes be ameliorated. It is possible, too, that applying a few extra inches of mulch will slow the warming of the soil, possibly delaying bud development just a tiny bit.
Training - Climbing roses, bourbon roses, hybrid perpetual roses, and some other roses make strongly vertical growth and will typically bloom at the end of a vertical shoot. Train canes at a more horizontal angle, about 45 degrees, or peg the long cane to the ground. This causes them to make 'laterals' and these lateral branches each form a bloom. The number of blossoms formed by a long can be multiplied by ten or twenty or more using this method. And the rose likes it.
Check References Some roses can take up to five years to get established, Sunset Celebration, for example. Others put a lot of energy into making a few roses , Parole, for example. Still others are just stingy. Check ARS Handbook for Selecting Roses, or the online resource HelpMeFind. (This item added at Cindi's suggestion below.)

Great list, Steve! Another factor, maybe...check Help Me Find or Roses in Review to see if the rose has a low rating. Possibly this rose is a stingy bloomer for everyone . I admit I check the ARS "Handbook for Selecting Roses" before every purchase. It doesn't help on newer roses, but the ratings have been real close to spot on.

Good idea. Thanks, Cindi.

I think the ARS handbook is frequently very helpful and I refer to it for almost every rose I buy. In the cases of some roses not widely distributed I think there might sometimes be a knot of people who inflate the ratings of certain roses. It happened with the Kordes rugosa Robusta two decades ago. More recently it has happened with a few minis, too. I also think that there are roses distributed far outside their appropriate ranges. These end up with ratings below 6.0 even though they might be very good in some tiny islands of perfect weather. HMF, if you read the comments by rose growers and look at where the photos come from, can sometimes be very helpful in determining whether a rose is more a Northern European rose, an Eastern/Plains State US rose, or a West Coast/Australia rose.