For purposes of this discussion, cold tolerance does not refer to freezing temperatures, but rather when the thermometer registers in the upper 30's to low 40's and heat tolerance refers to the ability to withstand weeks upon weeks of at an ambient reading of 95^o F. with little or no cloud cover.  The continental climate of South Texas with wide variations in temperatures is challenge number one.  It very seldom freezes here, but during the months from December through February, we can experience dry northers with strong winds - these wreak havoc with banana leaves.  The summer months from mid-May through early October have incessantly high temperatures, often with weeks on little or no cloud cover.  These can cause leaf burn, and, if the plants are not watered regularly, can result in the loss of the meristem.  For a more detailed discussion of the climate, see Part I.
        Challenge number two are the soils.  While the soils of the Lower Rio Grande are alluvial and deep, they are subject to hardpan formation if exposed to the tropical sun.  They respond very well to copious quantities of organic amendments.

        We experienced ten years of below normal rainfall from summer 1993 to August 2003.  I won't recite endless statistics, just to say things were quite dry and normally warm summers were even hotter.  The cultivars that did the best under these conditions were Dwarf Brazilian and Raji Puri; the cultivars that did the worst Gran Nain and Super Dwarf Cavendish.  September, 2003, brought a change in the weather patterns - in six weeks Brownsville received over one year normal precipitation.  The total for the year 2003 was a whopping 32 inches of rainfall.  My banana plants started to revive!
         This past winter (Dec.-mid-Feb.) has been cool, not cold, with lots of cold fronts, both wet and dry.  The lowest temperature in Brownsville has been one night at 37^o F. on a clear night.  I'd rather deal with calm and cold than 42^o F. and a strong northwest wind.

            There are two keys to banana horticulture in South Texas:  soil moisture and protection from the searing sun.   All plants are heavily mulched with homemade compost and manure.  During the summer months the high temperatures cause rapid decay of organic matter.  I am constantly adding new compost.  Watering is constant, even during the winter months.  The rich, damp organic matter encourages earthworms.  I do not use chemical fertilizers as I am worried about raising the pH and increasing the soil salinity.
            While most handbooks recommend planting bananas in direct sun, this can cause leaf burn and death of the plant in the hot South Texas summer.  I have even lost Rajapuri during the height of the drought when I did not water for a week or so. The Cavendish clones are extremely susceptible to leaf burn, particularly Gran Nain.
            In terms of cold protection, I do nothing, but try and plant in a location that does not get the direct hit from the northwest wind.  At the end of the winter (mid February), the leaves of Rajipuri and Dwarf Brazilian seem to have less tears and yellowing than the Cavendish varieties.  They will also put out new leaves during the cooler winter months.  Gran Nain, which I no longer grow,  gets burned anytime the temperature is below 50^o F. combined with a 15-25 mph northwest wind.  Mahoi, if it is in a protected location, seems to do okay in the winter.
            After much experimentation, I am now limited to three cultivars:  Dwarf Brazilian, Rajapuri, and Mahoi (Double) from the Cavendish cultivars.  In November, 2003,  I received, from Stokes Tropicals, a '1780' which is grown in Louisiana.  I have no idea what it is, but it will be planted this weekend.  Hopefully, it will fruit by October or November of 2004 and I can report on just what it is.
            Many people ask why I do not grow Orinoco.  It is the best adapted to South Texas and they have basically become native here.  They grow like weeds and can actually come through a frost with no leaf burn.  It is not a challenge to grow them, I don't like the taste of the fruit, and, most important, they have a tendency to take over my small yard!  Orinocos of the bananas and Washingtonians of the palms are my least favorite plants.