Plant a Pluot Now

In the dead of winter, gardens succumb to dormancy. Long gone are basket-in-hand harvest jaunts to the vegetable plot. Instead, pumpkins lay forlorn atop the compost pile. Even late season delicacies like fried green tomatoes seem a distant memory. Clouds form, rain falls, and we turn inward. But what’s a gardener to do? Reclaim the winter and celebrate bare-root season by planting summer fruits now. By January, nurseries in Marin, Sonoma, and Napa counties are abuzz with a daunting selection of fruit trees. You’ll find all the standards—apples, pears, plums, peaches, and figs—as well as offbeat, newer options like the pluot.

What is a pluot (or a plumcot or an aprium, for that matter)? Crisscrossing semantics have left consumers perpetually confused by these three fruits, so let’s take a moment and demystify.In the late 19th century, Santa Rosa’s very own world renowned horticulturist Luther Burbank created the plumcot, a 50-50 cross between a plum and an apricot. Far from a perfect fruit, it never quite took hold in the market. Then, in the 1980s, brilliant plant breeder Floyd Zaiger (of Zaiger’s Genetics in Modesto) did his own tinkering. Using Burbank’s plumcot creature, he backcrossed it with the plum to create a pluot, then with the apricot to produce an aprium.

In the end, both fruits are still plum-apricot crosses but the pluot contains more plum traits and the aprium more apricot. Concerned citizens who avoid genetically-modified foods need not fret: pluots are hand-pollinated and safe to eat. But why go to all this fuss? Aren’t plain old plums sufficient?

If you’ve sampled a pluot, then you’ve had your “aha” moment. It starts with visual lust and ends quickly with a sucked-clean pit. First off, they are fascinatingly beautiful. Skin color ranges from chartreuse to purple, golden to magenta, dappled to streaked. Slice one in half to discover a contrasting hue within! This bicolor boon makes pluots ideal candidates for stunning tarts and savory salads (with fennel and rocket and feta, oh my!). But the real reason pluots reign supreme is their complex flavor and texture. Sure, our sugarbiased tongues can’t deny their sweetness over plums, but a pluot has more to offer than mere sugar. Its unique lineage results in tastes on the tongue and feelings between the teeth that are truly virginal.

Think about the difference between the simplicity of a Beaujolais versus a well-aged Bordeaux…or the flavor of plain melted butter compared with that which has been browned. The parallel holds true for the plum versus the pluot: in repeated taste tests, pluots reign supreme.

Two Keys to Success

As far as fruit trees go, pluots are a recent arrival in the retail nursery realm so don’t be surprised if you need to dig around a bit to find them.

You may also hear ramblings about our area offering insufficient “chill hours” to support a pluot. Chill hours—a number on a fruit tree tag in the 200-800 range—simply refers to the amount of cold required for the tree to properly set fruit. It’s true that a microclimate that is a combination of very mild (low chill hour) and extremely foggy (low sun) is not ideal, but most Marin, Sonoma, and Napa microclimates are excellent fits for pluot culture. That said, it’s still wise to stick with those in the low-chill department. See below for a list of which varietals work well here.

The other crucial issue to success with pluots is providing a pollinator. Pluots are not “self-fruitful,” meaning that they require an external pollinator to set fruit. Merely one selffruiting Japanese variety plum (like Santa Rosa or Late Santa Rosa) planted within 100 feet of a pluot will do the job.

Bare-Root Planting Tips

A bare-root fruit tree means precisely that: its roots are not planted in soil.

Bare-root planting season happens exclusively in winter because plants are in a dormant (or hibernation) state. Since they are not actively growing, they can tolerate being dug up, transported, and “heeled in” at the nursery. (“Heeling in” is a quirky farming term referring to a temporary planting situation in which the roots are covered in loosely-packed soil medium until a permanent home is found.)

It’s difficult to argue with the merits of bare-root season. The selection is staggeringly better than during the growing season, and the prices are usually far lower than what you would have to pay for the same tree leafed-out and potted-up two months later. Bare-root trees also get a healthier start because they avoid the woes of being transplanted.

When choosing a bare-root tree, be sure to check the roots. Seek out a tree with an even spread of strong, stiff roots and avoid those with either dry, brittle roots or squishy and rotting ones.

Before planting, trim away any cracked or suspicious-looking roots. Some gardeners swear by an overnight pre-planting soak in lukewarm water; others wing it and skip this step. But don’t bend the rules on sun and soil—most fruit trees (including pluots) require six to eight hours of full sun a day and extremely well-draining soil (no clay, please!).

Dig a hole that is two times the width and height of the root system and amend copiously with compost.

Next, build a well-packed mound of soil to support the roots; the height of the mound should boost the crown of the plant just level with or slightly above the eventual soil surface. Backfill halfway with soil, tamp down, water, and adjust the tree before filling the rest of the hole.

Growers highly recommend protecting young bare-root trees from sunburn with the help of latex tree trunk paint. After planting, simply paint the tree from the base to the top. Reapply as necessary every year until the canopy shades the trunk.

Basic Pluot Care

Pluots ask for the same basic care as plum trees.

• For the first few years, be sure to pamper a tad with water—once a week during the growing season—but after the tree is established, back off to infrequent but deep irrigation.
• Mulch as often as necessary to block weeds around the base of the young tree.
• Feed twice a year (early spring and late summer) with compost or an organic, balanced (10-10-10) fertilizer.
• Pluots are prone to aphid attacks and various fungal foes. For a mild aphid infestation, simply use a high-pressure hose to spray them off or nontoxic neem oil and insecticidal soap; extreme cases may require dormant oil spray. Fend off fungal problems with a preventive approach: twice a year (in fall after leaf drop and in early spring before buds form), spray the tree with lime-sulphur or copper.
• Fruit trees absolutely require pruning to stay healthy and produce plentiful and high-quality fruit. Although many gardeners neglect pruning, it is the most important pampering you can give your fruit tree.

If you purchase a pluot tree at a local nursery, chances are it came from wholesale grower Dave Wilson Nursery in Modesto that specializes in fruit trees. Coining the concept of “backyard orchard culture,” the folks at Dave Wilson are revolutionizing access to fruit in our own gardens. The nursery encourages gardeners to ditch the concept of large, burdensome, hard-to-prune trees and to instead keep them pruned extremely low and densely-planted (four trees in one planting hole!). For detailed information, visit the very informative Dave Wilson Nursery website (www.davewilson.com).

Perfect Pluots for Our Climate

Dapple Dandy: A consistent taste-test winner with dappled maroon and yellow skin and a creamy red flesh within.
Emerald Drop: Chartreuse skin and honey-flavored yellow flesh.
Flavor Finale: A fall-bearing type with purple skin, amber flesh, and exceptional flavor.
Flavor Grenade: A striking green-red taste-test winner with crisp texture and explosive flavor.
Flavor King: This hands-down repeat taste-test winner boasts classic red plum looks and sweet but piquant flavor.
Flavor Queen: Boasts a long harvest season, bright green skin, and super sugary golden flesh.
Flavor Supreme: A flamboyant-looking taste-test winner with green skin and blood-red flesh.
Geo Pride: A heavy producer with pinkish skin and yellow flesh.
Splash: Bright golden heart-shaped fruits.

Luther Burbank’s Plumcot

In this day and age, we take creative hybridizing for granted. It’s no shock to encounter a brand new fruit amongst everyday produce like it’s been there forever. Back in the early 1900s when Burbank first introduced the plumcot, however, the notion of such crosses was practically heretical. This pivotal moment in his career is captured in the following excerpt from his notes entitled, “Accomplishing the Impossible: The Plumcot. A Cross Which Man Had Said Could Never Be Made.”

Several years ago a party of noted scientists from various parts of the world were visiting my nursery. I asked one of them, an American, even then well known to the public as an authority on horticultural subjects to come over to another part of the grounds and see one of my crosses between the plum and the apricot.

“There can be no such fruit,” my visitor declared. “The two species are wholly different in all respects. Everybody knows it is impossible to cross two trees of such widely varying types as the plum and the apricot.”

“Well, what kind of a tree do you think this is?” I asked a moment later.

After a long and thorough examination, I heard the reluctant decision: “Well, it surely is what you claim it to be—a cross between the plum and the apricot. I never thought it could be made.”

When the apricot and plum were crossed to produce an intermediate fruit, the accomplishment was thought by some botanists to savor of a violation of the laws of nature. This belief has undergone a radical change in recent years and the many combinations of widely different species made on my Sebastopol grounds have had at least a share in broadening the views of the classifiers. Visit Harmony Farm Supply and Nursery in Sebastopol or on line at www. harmonyfarm.com for an extensive selection of Luther Burbank cultivars.