Q.
I was so happy to see an article you recently wrote in the RJ concerning bitter
orange trees. I have one that was here
when I bought my house 16 years ago. It
was in a patio pot at that time and I had it replanted, along with a Meyer
Lemon, in the “alley” between my house and my neighbor.
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| Bitter orange tree planted in Las Vegas. |
My lemon has been giving me fruit for the
past approximately 8 years and about 30-35 lemons. My orange tree has always produced flowers,
but no fruit up until 2 years ago. I got about 25 nice sized oranges. Last year I got flowers but Not A SINGLE
fruit. Is this a tree that may “skip” a year in fruit production? I have done nothing to these trees except
fertilize with Arizona Best’s Citrus fertilizer Valentine’s Day, Memorial Day
and Labor Day.
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| Myers lemon (not readers) planted in Las Vegas. |
A.
“Skipping” a year is called “alternate bearing” and occurs, usually, with older
varieties of fruit trees like some almonds and apricots. Bitter orange, like
most oranges, produces the majority of its flowers in the early spring. This is
the same time we experience freezing weather. Your fruit loss could be because
of freezes.
Did You See Flowers?
It is important to ask, “Are you sure you
saw flowers in the spring and no fruit?” That’s an important consideration. If
you did then it was a failure to set fruit. That is either because no
pollinators were present (bees and other pollinators like flies and moths) or
it froze several times in a row in the early spring.
No Flowers
If you did not see flowers in the spring,
then it was because it never flowered. That could be because of some hard
pruning that was done, and the tree is recovering, or too much fertilizer was
applied too often. This is true particularly of high doses of nitrogen
fertilizer such as ammonium sulfate (21-0-0). In either case, the tree grew so
vigorously that it never flowered!
Fertilizer Applications
Normally one fertilizer application is all
that is necessary, or two at the most. If two is applied, then apply half of
your normal fertilizer application in the early spring and half right after
harvest. If harvest is close to your early spring application time then apply
fertilizer to citrus just before it gets hot in the early summer. Avoid making
fertilizer applications when it is hot. In the case of citrus that might
freeze, avoid fertilizer applications after July.
Tree Surrounded by Rock Mulch
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| Some citrus okay with rock mulch. |
I noticed that the tree is surrounded by
rock mulch. Yet it has good color. Citrus of all types don’t usually like rock
mulch all that much. The first thing to go is dark to medium green color in the leaves when it
gets unhealthy. That’s why I was surprised with your tree. Maybe your choice of
fertilizer helps.
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| Some citrus not okay with rock mulch. Use amended soil when planting and citrus fertilizer every year. |
Citrus are from southeast Asia and China.
They prefer to grow in soils with a higher organic content than most soils
covered in rock. Along with your fertilizer application try raking back the
rock at least three feet all around the tree and applying compost or wood chips
to the top of the soil. Water it in and rake the rock back on top of it after
it is watered. Do this about every year or every other year at the least. I
think your bitter orange will like this type of soil better than soil covered
in rock.
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| Pomello on our farm in the Philippines. |