QuestionQUESTION: After 3 years I finally propagated my minature rose with leaf cuttings. I am in Zone 4 and it is now Oct. 1. How do I winterize the cuttings as it gets too cold outside in our winter. The answers I have heard are 1) put them under a grow light 2) harden them my putting them in the basement with not light 3) put them outside in a cold frame 4) put them outside and cover them with straw.
ANSWER: Zone 4 is rather cold to put mini rose cuttings outside even if they are well protected. Putting them under lights will make them grow quickly into nice bushes but you will have to keep them moisturized by spraying daily as house temperatures are too dry for mini roses. Or for that matter, any roses. A cold frame works well but these suggestions you got are mainly for the larger garden roses not the tiny ones with the thin canes which can freeze quickly. I would put them in an area of your home which doesn't get any heat, such as a cold basement but the temperature should not go below freezing. 34' to 38' is what the temperature should be as the roots will grow even when the temperature is around 40' Cover them right up so that only a couple of inches are showing above the soil or the material you use. If you have the space, a fridge is ideal. Just wrap them in a black garbage bag to block the light.
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QUESTION: Thanks for the great advice. It is now Oct 3rd and I was wondering when to but them in the basement for winter, what month do I bring them out of the basement, and finally do I need to give them any water during that time. I know if I leave dahlia bulbs too long in my basement they will rot. Also (sorry I am retired and want to have gardening as my hobby so I have too many questions) I am going to leave some of my roses (comparison experiment) upstairs under a grow light (with spraying} can I just put them outside when spring time comes without any winterizing?
cheers, and thanks
AnswerKeep your rose cuttings somewhere sunny and cold so they will go dormant and drop their leaves. Then put them in the basement. Give them enough water to make the soil damp but not really wet as that will cause a fungal problem and the cuttings will die. It not a big problem if you forget and don't water for a while as the cuttings are dormant and don't need water. All you want to do is make sure the rose roots don't dry out and die. Roses or any plants that have been grown under lights are frail plants and think they are in California. Putting them outside too soon will surely kill them. When the weather warms up in the spring take them out of the lights and place them on a window sill. Then later on place them outside in the sun where they are sheltered and bring them in before it gets cool. Do this until the late days warm up and they should be fine outside. Be sure to let me know how your cuttings do in the different situations.