A friend asked me some questions about growing roses from tiny rootings. I answered her below:
I sent 4 band-size rootings to my sister in Idaho, and she soaked them in water and killed them. It took me 4 months to root those, and she killed them in 1/2 hour soak in water. Soaking roots in a bucket applies to GRAFTED bare-root (dry sticks), but it will kill cluster roots instantly. Just 10 min. soak of cluster-roots like petunia, marigolds, or tiny own-root roses is enough to damage them.
Gallon own-root or solid band-size can be planted smack into clay, but for tiny roots that haven't become solid, it's best planted in a pot to be winterized in a dark & unheated garage in my zone 5a.
I kept tiny rootings inside my garage and they survive winter if it's in a fast drainage potting soil. Fast drainage soil with lots of bark like Pennington Potting soil at Walmart won't freeze to an iceblock to kill tiny roots.
The top of the pot should be dense minerals (like clay mixed with gypsum to fix pale leaves, or clay mixed with lime for already dark-green leaves). The bottom is best with fast draining soil with bark chips. MG-moisture control potting soil is fast draining but with zero nutrients, I still need to top the pot with my clay mixed with lime (if leaves are dark green), or clay mixed with gypsum (if leaves are too pale).
As to breaking up hard clay with pelletized lime (yes for dark-green leaves like Dee-lish only). For pale leaves like Evelyn or W.S. 2000, it's best to top with clay broken up with gypsum (has sulfur to turn leaves dark green).
Mixing in potting soil with lots of bark chips (like Pennington) works well with clay but mixing 100% peat moss potting soil with clay turns into concrete. Peat moss breaks down and glues up with clay. Peat moss potting soil is too dense and will choke roots
Roots need oxygen to grow. If the potting soil has lots of bark chips (like Pennington now on sale for $4 at Walmart), then it will create spaces in clay for roots to breathe. From the web: "An ideal soil contains 25 percent air, 25 percent water, 45 percent minerals like clay and 5 percent organic matter."
The best way for tiny rooting to survive my zone 5a winter is with fast-draining potting soil with bark chips mixed in, or MG-moisture-control potting soil. These are dry & fluffy & lots of air space for root growth, and has small bark mixed it.
Roses will survive my zone 5a winter in a pot, in unheated garage if the soil doesn't turn into a block of ice from being too wet. The many bark chips in fluffy potting soil prevents it from frozen into a block of ice to kill roots.
Best chance of zone 5a winter survival is put dry & fast-draining potting soil in a pot, then top with my clay mixed with 1/2 cup gypsum, and let rain water dilute that (or at least 3 waterings), that will dilute the sulfur so it corrodes the soil in advance.
If I mix gypsum into clay and top a tiny rooting with that, the acid from the gypsum will corrode that tiny root. Acidic Sulfur helps leaves to be dark-green and for fast growth, only if mixed IN ADVANCE into soil and let several watering dilute that acid.
Alfalfa meal has sulfur for dark green leaves but will burn plants with its acid if a wad is put on top of the crown. Alfalfa meal is best diluted and soaked in alkaline tap water to release sulfur, then water roses so their leaves can be dark-green.
Same with sulfate of potash with 21% sulfur, I killed a band size Felicia by putting sulfate of potash directly on it. It's too acidic. In contrast, my roses in pots become constant bloomer when I DILUTE the sulfur by using 2 TBS of alfalfa meal plus 1/2 TBS sulfate of potash for potassium in one gallon of tap-water.
Prior to all day rain, I topped my 20+ pots last year: each 3-gallon pot gets 1/3 cup of alfalfa meal and 1 TBS of pelletized lime. Can't use gypsum during rain since it's too acidic. Gypsum is meant to mixed into soil for pale rose 1 week in advance PRIOR to planting.
Below is Augusta Luis after 2 months of purchase as band-size own root from LongAgoRoses. I mixed in gypsum a month in advance, plus I topped it with pelletized lime and alfalfa meal during heavy rain. It's a calcium-hog with zillion of petals:
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Beautiful irises with companion plants
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