Texas Citrus Rootstocks
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In Texas, a few different rootstocks are available for citrus growers, and depending on the conditions where the Texas citrus grower is producing oranges or grapefruits, one rootstock may be preferable to another.
Of course, the sour orange rootstock is the most common Texas citrus rootstock for any number of reasons, but there are others. Knowing the characteristics of the available rootstocks goes a long way in understanding why a grower may prefer one over another one.
Swingle citrumelo is a rootstock known for yielding high volumes of fruit, and it is a very capable rootstock for Texas citrus production. That being said, growers should consider that it is best limited to sandy soils with good drainage.
Heavier soils are much less suitable for this rootstock. Given the right conditions, however, swingle citrumelo provides great resistance to several viruses like xyloporosis and exocortis, and many growers will find success with it.
Citranges are rootstocks that are also very capable of producing good results in many parts of the Rio Grande Valley Ã the Texas citrus region where the state's grapefruits and oranges are grown. Growers should keep in mind that citranges are less tolerant of soil alkalinity than the sour orange rootstock, and are less cold-hardy. Still, a considerable percentage of Texas citrus fruit is produced on a citrange rootstock.
It's the sour orange, however, that is the most common rootstock for Texas citrus like oranges and grapefruits, and there are any number of excellent reasons for this. It's quite cold-tolerant relative to other rootstocks, and it has, for many years, been well-adapted to the climate and soil conditions of the Rio Grande Valley. It may not produce yields as high as swingle citrumelo in all circumstances, but its overall tolerance for conditions like poor drainage makes it suitable for the majority of Texas citrus applications, and upwards of 90% of orchards in the Rio Grande Valley make use of the sour orange rootstock for their production.
While it's unlikely that there will ever be a better Texas citrus rootstock than sour orange, the citranges and swingle citrumelo rootstocks are completely acceptable for growing oranges and grapefruits under the right conditions. Growers, of course, are the experts when it comes to knowing about the particular conditions in their area of the state and what rootstock is most amenable to the kind of fruit they are growing and what they would like their production to be. After all, rootstock is just one consideration among many that a grower must make.