Great article on growing citrus in the Arizona valley with Brian Whitfill & John Babiarz

Citrus trees depend on timing, sunlight to thriveDebra Gelbart - Mar. 14, 2006

The almost intoxicating fragrance of the blossoms, the canopy of shade and the delicious fruit that citrus trees produce are just three of the reasons that Arizonans still have a love affair with orange, grapefruit, lemon and tangerine trees, and want them in their yards.

"My grandfather moved to Phoenix from Texas in March of 1928 when the place was abloom with citrus, and he thought he was in heaven," says Brian Whitfill Blake of Whitfill Nursery. "This is one of the best regions anywhere to grow citrus, because of our warm days and cool nights, and because we have fewer pests that grow on citrus. The citrus grown here has a higher acid content than that grown in Florida. The higher acidity is what gives a navel orange that crunchy, crisp taste."

Tips for buying

Although many of the citrus orchards that were in the Phoenix area 20 and 30 years ago have given way to residential and commercial development, there still are places to purchase the trees. In addition to Whitfill, with its three Valley locations, Greenfield Citrus Nursery in Mesa has been selling to the public since 1980 and has up to 15,000 citrus trees in production at any one time.

Don't buy a citrus tree as a seedling, Blake and John Babiarz, owner of Greenfield Citrus Nursery, say.

"If they're too small when you buy them, you're babysitting them," Babiarz says. "It takes an orange tree, for example, about four and a half years from its very beginning to reach marketable size. Most citrus take about six to seven years from inception to production." Allowing trees to produce at too early an age can cause limb damage and improper development of the tree's branches, he says.

Buy older trees

A better plan, Blake says, is to buy a citrus tree that's at least three years old and preferably four. "With a five-year-old grapefruit tree, for example, you may be able to harvest fruit the first year," he says. In metropolitan Phoenix, many varieties of citrus thrive, including navel oranges, Valencia oranges, Minneola tangelos, Ruby-Red grapefruit, Marsh grapefruit, Oro Blanco grapefruit, lemons, limes and tangerines.

What's a rootstock?

Citrus tree buyers may not know about rootstocks, but Blake and Babiarz say they're important considerations. Most citrus types and varieties don't perform well on their own root system, so they are commonly budded onto rootstocks that are better adapted to certain soil conditions. The very best rootstock for the Salt River Valley is the Seville sour orange, Babiarz says, adding that sour orange rootstock performs best in clay soil (like that found in much of the Valley). He relies on sour orange for the trees he grows.

But many citrus tree suppliers are turning to Carrizo rootstock. Sour orange and Carrizo rootstock typically result in tree life of about 100 years.

Blake warns orange tree buyers against Volkameriana rootstock. "Volka only works with lemons, limes, tangelos and grapefruit," he says. "If you use Volka rootstock with navel orange trees, you'll have beautiful looking fruit but it will have dry flesh," he says. Blake and Babiarz suggest you ask about the rootstock used in the tree you buy.

Whichever variety of citrus you choose, Babiarz says you're sure to enjoy it.

Planting pointers

Understanding the basics of planting and maintaining citrus trees will go a long way in assuring that your new purchase will thrive in its new home.

It's important to plant a citrus tree where it will receive at least four to five hours a day of direct sunlight, says John Babiarz of Greenfield Citrus Nursery, adding that the ideal time of year to plant is fall.

Water your new citrus tree once or twice a week for the first couple of weeks after planting, says Brian Whitfill Blake of Whitfill Nursery. After that, once-a-week watering should suffice through summer. "A common mistake people make in winter is over-watering," Babiarz says. While a mature (20-by 20-foot) tree uses 200 gallons of water per week in the summer, the same tree uses only 25 gallons in the winter. To conserve water, you can use your laundry water and pool backwash water to irrigate your citrus trees. With a hose or drip system, watering in the summer should take about one hour per tree, Babiarz says, explaining, "You don't want to water too quickly." He suggests soaking the entire root system weekly from the trunk to about one foot past the outside edge of the green canopy. Watering every day can lead to root rot, he says.

"You can lightly fertilize your new tree monthly," Whitfill says. An established tree-one that you planted two to three years ago-should be fertilized about three times a year, in February, May and September.

Prune your tree once a year-preferably at the end of February or early in March, Babiarz says. He and Whitfill don't recommend pruning the tree so the trunk is exposed, but if you do, you must paint the trunk to keep it from getting scorched by the sun. "Cutting off the lower branches can take away some of the best fruit," Babiarz says. "The best fruit is farthest away from the sun." He also doesn't recommend cutting away dead wood between prunings. "Once the tree begins to produce fruit, the branches begin to sag from the weight. The dead wood underneath helps support those branches and keeps them from breaking."