Washington navel is one of the two most commonly grown oranges in California. It goes a long way back, arriving in California in 1873. Navels have a bright orange color and an excellent taste and are great for eating out of hand. They have thick rinds that are easy to peel. Inside, the segments come apart easily. There are no seeds in navel oranges. Growing Washington navels in your backyard is an ideal way to get as many of the oranges as you want. The key to success is to learn what type of soil you have because California is home to sandy, clay and loam soils. Once you know, you can make the necessary amendments to make the soil more conducive to orange tree growth.
Choose a planting spot that faces the south. This is the sunniest location and Washington navel orange trees thrive with six to eight hours of sun daily.
Take a sample of soil to determine the pH. Use a pH test kit obtained from a nursery or cooperative extension. Washington navel likes between 5.5 and 6.5 pH. Gather a few samples from the planting area and mix them together. Send the soil to the cooperative extension for results.
Determine if your soil is sandy, clay or peaty. Hold some in your hand and squeeze it. If water drops out, you have a claylike dirt. If it's very dry, it's sand and if it's somewhere in between, it's peat soil. The soil in Southern California mountain and coastal areas tends to be sandy. Loamy soil is found in California valleys and plains. Cities and suburban areas in the state are likely to have clay soil because contractors use it to fill in areas when constructing subdivisions.
Change the soil so that it falls between the desired pH level. If you need to reduce the pH to make the soil more acidic, mix in 1.2 oz. of ground rock sulfur per square yard for sandy soil and 3.6 oz. per square yard for other soil types. This will drop the pH by 1.0 point. You can also use leaf mold, composted leaves or sawdust to accomplish the same thing. Make the soil more alkaline by combining hydrated lime. Mix in 4 oz. per square yard if you have sand, 8 oz. for loamy soil, 12 oz. for clay soil and 25 oz. per square yard for peatlike soils.
Make sandy soil more moist to grow Washington navel orange trees. This type of dirt has 80 to 100 percent sand. Add organic material like compost to make it retain water better. Till the compost into the sand until they are mixed well.
Lay down 6 inches each of builder's sand and compost to transform clay to a more neutral type of soil. Till the substances to thoroughly combine.
Avoid changing loamy soil. It has a good mix of clay, sand and silt for growing Washington navel trees.
Make a hole that is the same depth as the orange tree's nursery container. Make the hole twice as wide so the roots have room to spread.
Take the Washington navel orange tree out of the nursery container. Put it in the middle of the hole and fill with soil. Press down to pack the soil.
Create a 4 inch tall berm around the base of the tree. This will act as a berm and hold water in. Make it 2 feet in width all around the tree.
Fill the berm with water. Give the orange tree water once daily for 10 weeks. If the weather in California is drier than normal, pay extra attention to watering.