Ask Mr. Smarty Plants

This USDA Plant Profile Map shows that Diospyros texana (Texas persimmon) is native to Hays County, so we know that the trees are in the right climate and soils. If there are no signs of distress on the non-blooming tree, like insect damage or curling leaves, we will have to look further for the cause of the lack of bloom on one.

First, following the plant link above to our webpage on this plant, let's examine the Growing Conditions and see if one plant is in a less advantageous place than the other, or perhaps not in enough sun.

"Growing Conditions

Water Use: Low
Light Requirement: Sun , Part Shade
Soil Moisture: Dry
Soil pH: Alkaline (pH>7.2)
Drought Tolerance: High
Heat Tolerant: yes
Soil Description: Well-drained, limestone loams, clays, and caliche.
Conditions Comments: North of the Rio Grande Valley where winters are cold, will usually be deciduous. From the Rio Grande Valley southward, will be semi-deciduous-to-evergreen, losing its leaves all at once in early spring like live oaks, with no period of bareness."

This says that the plant requires sun (6 hours or less of sun a day), or part shade (2 to 6 hours of sun a day). Blooming plants always bloom better in full sun, but it should certainly be blooming a little bit. We don't know at what age these trees normally bloom, and that will vary because of sunlight, moisture, etc. When the trees were purchased, one may have been more mature than the other. Also, if one has accidentally been fertilized when grass was being fertilized with a high nitrogen fertilizer, that could have encouraged leaf growth and discouraged flower growth. Avoid fertilizing native plants, they generally do not like it. And, finally, some damage may have been done to the plant when it was transplanted, a broken root or not enough root ball dirt around it. Transplant shock can occur years after a plant has been put in the ground, but usually is not fatal, unless the tree was already diseased or damaged.

From eHow.com, we found this information on blooming for the persimmon:

• The USFS indicates that the persimmon tree waits a decade or more before it begins to bear fruit. The persimmon blooms will produce edible fruit after approximately 10 years, although the optimum fruit-bearing age for the tree is between 25 and 50 years. The tree should only be expected to provide an exceptional crop about every two years.

From Sex Among the Persimmons:

"If you happen on a persimmon tree in the spring, check for flowers. You’ll find them on this spring’s new growth that is emerging from one-year-old limbs. The flowers form in the axils of the new growth – that’s the angle between a leafstalk and the branch the leaf is attached to (see the photo in the gallery below). Female flowers are slightly larger than males, and they are attached closer to the branch, because as the fruit forms and becomes heavy, a strong anchor to the branch will be necessary (again, more photos in the gallery). In contrast, male flowers dangle on a stem and almost appear like tiny bells (I promise I’m trying to keep this G-rated). Male flowers also have a “calyx” (the leaf-like cup that holds the flower) that is smaller than the flower. In females, the calyx is roughly equal in size to the flower. Finally, male flowers occasionally, but not always, form in clusters of two or more hanging from the same axil. Female flowers do not. If you see dangling persimmon flowers in a cluster of two or more, it’s a male tree."

Prescription: Patience