Gila Valley

The Gila Valley is an ideal area for research into cold hardy citrus. The climate in this valley is such that citrus grows well, but is regularly subjected to freezes that will kill non cold-hardy citrus varieties. The climate allows us to test which varieties can survive these low temperatures.

Greenhouse

In our greenhouse, we will be able to grow numerous citrus plants to the size required for cold hardiness screening. We will also be able to conduct citrus breeding in the greenhouse.

Research (The Scientific Explanation)

Our research focuses on developing cold-resistant citrus varieties. Because cold hardiness in citrus is a “quantitative trait”, we can improve cold hardiness with each generation as we concentrate and focus cold hardiness genes from multiple citrus varieties into each new generation. Thus we can expect to develop varieties that are slightly more cold hardy than current varieties at first but with each generation of breeding we can improve. There will of course be a limit to what we can achieve — we don’t expect to ever be able to create citrus varieties that can survive in very cold climates such as Montana or Greenland. However, with multiple generations we can eventually develop varieties with significantly improved cold hardiness.

Because the period of time from one generation to the next in citrus is very long, we will focus on techniques that can shorten the citrus “juvenile period” to shorten the period from one generation of breeding to the next.

It is important to note, however, that even with advanced methods, this will be a long-term effort. Part of the reason that there aren’t a lot of cold hardy varieties of citrus available is because developing cold hardy citrus is a difficult and long term project. To succeed will require resources and a sustained effort. The Cold Hardy Citrus Foundation is dedicated to succeed in this effort.