Growing Rice in Portland, OR
Rice is a subtropical and tropical plant and can be easily damaged by low temperatures at any stage of growth from germination to maturity. That makes it challenging to grow Rice in Portland area growing season. The only reference I found of rice production in Willamette Valley is of Wild Rice varieties. Wild rice is harvested green unlike the cultivated rice which needs field drying. Any naturally low/wet areas with our local heavy clay soils will be well suited for wild rice production. Here is the link to article on wild rice production in Wilamette Valley http://www.oregonlive.com/foodday/index.ssf/2012/01/willamette_valley_clay_soil_is.html
Among cultivated varieties, long grain indica varieties are not suited to local growing conditions. However, it might be possible to grow some japonica varieties under irrigated conditions.
I hope this information helps. Please let us know if you have further questions.
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