Question:
I bought a house with two red maples in the front yard. Each year, they start a brilliant red color, but they fade to green by the end of the summer. Is there a special fertilizer necessary to keep them red all year? Someone said the color reverts to green because photosynthesis can't occur in red leaves.Answer:
- I'm assuming that your red leaf maples are Japanese Maples. There are other types of red maple varieties. They have green leaves that turn red in the fall and are used as shade trees.
- The number one cause of Red Leaf Japanese Maples fading to green during the growing season is not enough hours of direct sunlight. In rare cases, constant feeding with high nitrogen fertilizers can be an issue. Red Leaf Japanese Maples should have six to eight hours of direct sunlight from April through October. Photosynthesis is where plants manufacture food and occurs in any leaf color except white. Therefore, leaf colors are genetic pigments, with green being the dominant one.
- The red color comes from the presence of sugars stored in the leaves. Some maple varieties produce and store more than others.
- The sugars in Maples are produced by photosynthesis. The Maples use the sugars for normal respiration and metabolic functions. The rate of sugar production is a function of the daylight hours, while the rate of respiration is a function of temperature.
- The red color is the strongest in the spring when the sunlight hours increase and the temperatures are still cool. This results in high sugar production and low consumption.
- Our longest days are in June. As the days get shorter, sugar production decreases while the consumption of sugars increases because of the higher temperatures
- As the sugars are depleted, the red color fades to green. Some cultivars produce more sugar or consume less; thus, they longer hold on to their color. Japanese Maples planted in shady areas produce less sugar yet they consume the same as one planted in the sun. Therefore, these plants will fade quicker.
Question:
Now that I've pruned my rose bushes, will it harm the plants to trim off the thorns?Answer:
- I'm curious as to what you think you would gain by removing the thorns? These bushes are not going to remain thornless for very long. The thorns would return with the new seasonal growth.
- There is no horticultural advantage in removing them. Instead, you're placing the plants at risk by creating entry points for stem diseases and invading insects. It is just a waste of time with little to gain from it.
- Instead, I would channel my efforts into removing all the remaining foliage, and the debris at the bush's base (es), and then spraying the plant(s)with a Copper Fungicide to control the overwintering fungal spores of Black Spot. Mildew and Rust. I'd also loosen the metal tag, so it doesn't girdle the stem where it's attached.