OK ... now you have got me going. I hate giving growing advice to gardeners who are gardening in really different climates than what I have personally experienced, but my training about roses is very different than even very experienced rose gardeners. I
had to learn the botany of roses and more, just to be able to talk to Ralph Moore and Kim Rupert because they did not dumb it down for me and I didn't understand what they were saying more than half the time when I first started working with them. Time to do my homework.
Ralph often said that if you grew a good root mass for a rose, it could withstand both heat stress, cold stress and water stress better than if you just popped the roses into the ground. That goes for both budded and own root.
When I was talking with Berling a couple of weeks ago, who worked for Ralph for 25 years before she started her own nursery after he closed Sequoia, she repeated his advice and said, "Grow roots the first year."
I never put manure or compost in the planting hole. The feeder roots of a rose are in the top 6 to 10 inches. If you put the manure and compost in the bottom of the hole, the rose won't use it because it only has anchor roots down there. With manure deep in the planting hole, you are taking a chance of damaging the roots with "salt burn". This is because all fertilizers are some form of salt. The soil bacteria works on the organic fertilizers to break their salts into a form that the rose can take up as the nutrients they need through reverse osmosis. The soil bacteria are most active near the surface of the soil.
I do use manures and compost on top of the planting holes along with mulch. As Kim says, "That's the way nature does it."
I always do a perk test on every planting hole because we can get 50 inches of rain in one season. If the hole doesn't drain, at least over night, the chances of having root rot after a very rainy winter are much, much higher.
During high temps, I do a deep watering once a week and what I call a feeder root watering mid week. When the temps are lower, I only do a deep watering once a week. The deep watering takes care of the needs of the anchor roots and the feeder root watering is providing water to the roots near the surface which take up the most moisture for the plant.
I also have to wash the roses down daily during the dry high temp period of summer to control spider mites. I usually do this in the afternoon and the roses will take up moisture through their foliage.
Since my night temps cool off at night, this is sufficient in a climate where my summer temps are usually in the high 90s and low 100s during the day. Yes, I can see some of the roses wilting in the afternoon, but that is because the transpiration rate from the foliage is higher than the rate which the plant can pull moisture up from the root zone. There's no fix for that except for shade. With the cooler night temps, the plant has time to catch up and by morning, the rose is no longer wilting.
I water deeply the day before I feed the roses because this reduces the chance of any fertilizer burn. In other words, take care of the roots. I don't do foliage feeding during the high temps.
I don't have die back in this garden, so others are more experienced than I am in this area. However, if the material you are using to protect the plants stays wet, you have a higher chance of disease and rot.
Your primary protection is to make sure you bring a healthy rose into winter.
This is just general information. I am trying to summarize what I have taken away from years of rose discussions with two men who are way out of my league as far as rose knowledge is concerned. If you have more questions, please feel free to ask.
Others who grow roses in your climate can probably tweak the information I have shared above.
I have a list of modern roses that are most likely to be cane hardy up to zone 5 without serious winter protection. Yeah, that's based upon lineage and does not take into consideration things like wind and hail storms. No, my list does not include recent introductions because I stopped buying new roses a while back, so I stopped researching ...
I hope this information helps.
Smiles,
Lyn
