Patient approach best with shrimp plant
Q: I have had a yellow shrimp plant for about six months, and it has been blooming beautifully right along. It is still blooming, but a bit more sparse. I was wondering if I should cut it back, and if so, how much?
A: Your yellow shrimp plant, Pachystachys lutea, is a bit tender to freezing temperatures. If you cut it back now and new growth appears, a freeze would kill the new tender growth. If we have no freeze, you'll have a much bushier plant come spring. A more conservative approach would be to enjoy the flowers now on your leggy bush and wait until the end of February to cut it down to about one foot high, let it grow into a bush and enjoy the flowers from late summer on.
Two possible reasons for absence of olives
Q: In 2006, I bought what I was told was a 1-gallon Arbequina olive tree through the Internet from Wayside Gardens in South Carolina. The tree is now about 12 feet high and has not yet produced olives. What do I need to do to make it productive? What fertilizer does it require? I live in Hudson on a canal, but the gulf water does not come near the tree.
Robert Concepcion, Hudson
A: Of the olives, Olea europaea, the cultivars (cultivated varieties) Arbequina and Koroneiki are usually self fruitful in about three years. Other varieties may take from five to 12 years and need a pollinator. So, either they shipped you an olive other than Arbequina or something is culturally wrong. Olives are extremely drought tolerant, however, some supplemental irrigation during dry times is helpful. Over watering could be a cause of no fruit set; they don't like wet feet. The salty condition should cause no harm, for they are quite salt tolerant. A quality citrus fertilizer would be helpful for growth, but won't make your tree fruit. Do not fertilize with a turf product, high nitrogen will keep your tree growing, but it won't want to flower, that could be a problem. Change your cultural practices if that was the problem, or plant a pollinator such as Pendolino. If all fails, you'll have a nice ornamental tree.
Time will answer question on mangos
Q: A few weeks ago in the Times, you said that an avocado grown from seed would take eight years to fruit and it would be better to get one that has been grafted. I have started two mangos from seed and they are 3 feet tall now. Would your advice about the avocado also apply to mangos?
A: Mangos, Mangifera indica, behave a little differently than avocados, Persea americana, do from seed. Mangos have a much shorter juvenile period, four years, half the time as the avocado. This means it will flower and fruit in about four years. Here is the catch though. Mangos are either polyembryonic (several embryos or seedlings from one seed) or monoembryonic (one embryo or seedling per seed). The poly types come true from seed, a clone of your tree. The mono types will revert back to one of the parents of your hybrid tree, this could be good or not so good. Oh, the suspense.