Blood oranges
Q: I have a 4.5-year-old blood orange tree in my yard.Β Itβs the healthiest (by leaf color, height, breadth) of all my citrus trees.
However itβs my only tree that wonβt bloom. I tried a bit of water stress this year but instead of blooming, when all my other citrus bloom, it just leafs out more. It is 10 feet tall, and 6 or more feet wide. Any advice on what I can do to encourage blooming? I had heard cutting off the tips of leafing branches would help, so tried that on some of the tree this year, but still not a single bud. The tree is on the east side of my house, planted about 6 feet from my wall, and so is well protected from freezing as well.
A:Β Some citrus trees take longer to start blooming than others. It could be that you need to wait another season or two before it begins to flower. Other than age, the three main factors allowing trees to bloom are sufficient water, fertilizer, and light. Assuming your tree is in full sun or nearly so, I recommend taking a look at how much fertilizer the tree is receiving. Based on the size of your tree, you would need to supply between 1.25 and 1.50 pounds of nitrogen per year. This amount should be divided into thirds and applied during the following time frames; the first application in January/February, the second in March/April, and the third in August/September. The last factor is water and based on your description this is not an issue. Just in case, the recommended irrigation schedule calls for water every seven to 10 days in the summer, every 10 to 14 days in the spring and fall, and every 14 to 21 days in the winter. Each time the water should reach a depth of 36 inches. This depth can be measured with a soil probe.
Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Questions may be emailed toΒ tucsongardensage@gmail.com
