Rose cuttings starting to yellow
This is my first time. Please be gentle. I blame it all on mother! She wanted some more roses so I took some cuttings, dipped them in a powdered rooting hormone and potted. Can't tell you what kind except that they have pure yellow and pure red blossoms. Took the cuttings in late fall. My success rate has been 50%. I have about 9 cuttings remaining in modified 2 and 3 liter plastic soda bottles so that they are aerated and watered from below. Soil medium is 50% potting mix and pearlite to facilitate water wicking from below.
Their diet has been 100% city tap water that sets for at least 24 hours to try to kill any chemicals in the water.
I spray with an insecticide/fungicide once a week and cornmeal sprinkled on top the soil mix to prevent fungi.
It has been 4 months since the cuttings were taken. They have been living under a mixture of regular and sunlight spectrum florescent lights for 12 hours/day.
Room temperature is 63F constant. Only 2 of the cuttings have shown any new top growth at less than 4" then stopped. The rest of them look just like when they were clipped except for the root growth. A couple of the cuttings are starting to show some yellowing on the leaves. I have bought some 12-4-8 general liquid plant food concentrate that I plan to introduce through the root system or should I make a leaf spray? Want to feed them enough to green up the leaves but not promote any new growth until they get transplanted outside in their new home in about 2 months. Is there anything else I should be doing to heal up the yellowing leaves. Took some pics for you but don't know how to post them.