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The Western Colorado peach growing area is characterized by semi-arid conditions with heavy soils, and high soil and water pHs contributing to severe leaf chlorosis. 'Redhaven' peach trees grafted to 17 rootstocks were planted in a randomized block design with 8 replications in 2009 at the Western Colorado Research Center. One of the objectives of this study was to evaluate the performance of the trees under Colorado climatic and edaphic conditions. Tree growth measurements and survival were recorded each year. By the third year after planting, trees showed different levels of foliar chlorosis probably caused by micronutrient deficiency aggravated by high soil pH. These trees were rated for chlorosis based on visual observation (0-10 scale) where 0= no chlorosis to 10 having almost total canopy chlorosis in appearance. Fruit data collected in the third year showed a significant (P=<0.0001 and r(2)=0.59) impact of rootstocks on chlorosis where trees on different rootstocks produced different levels of chlorosis. The highest chlorosis was observed with 'HBOK 10', followed by 'KV010-123', and 'KV010-127'; whereas many trees on rootstocks such as 'Viking', 'Atlas', 'Guardian (R)', 'Mirobac' (aka 'Replantpac') had lower chlorosis levels and most of the others were intermediate. Tree circumference was significantly affected by the chlorosis (P=0.004). There was no impact of chlorosis on total fruit yield per tree, total number of fruits per tree, individual fruit weight, or incidence and severity of Cytospora canker among the trees grafted to different rootstocks. Trees on rootstocks such as 'Atlas', 'Fortuna', and 'Mirobac' had 100% disease infection. The majority of rootstocks had at least 12.5% tree death except 'Viking', which had 50% mortality. Tree death on 'Viking' occurred during the first year after planting; whereas most other trees on different rootstocks died in the second and third year due to Cytospora Canker.