The inland foothills of Orange County are part of what is called the "AVOCADO BELT" of California.  Avocados are native to Guatamala, eastern Mexico and the West Indies, and there is no mistaking Orange County for these climates, however the belt is the best we can do.  The hills are fairly free of frost and the inland temperatures are needed for good production.  For farmers, Avocado is one of the riskiest ways to make a living as the trees are quite exacting in their requirements.  Often, being lucky is just as good as being experienced.  As long as you are not trying to make a living out of it, an Avocado tree in your garden anywhere in Orange County can be a low maintenance luxury.

A typical healthy Avocado tree grows to 12-20' tall and wide, with a dense rounded  evergreen crown of large, deep green leaves.  A good tree produces about 100 fruit per year and can be harvested over a 3 to 5 month period. 

Avocado trees require ample moisture at all times as well as perfect drainage.  Avocado roots are highly subject to rot disease if water stagnates around them for more than a short time.  This means that your soil where the tree is to be planted has to be either very sandy or right at the edge of a cliff (a raised planter or raised mound can also suffice).  One method of checking drainage is to dig a hole about 1' wide and deep and fill with water.  If it drains away within 15 minutes the drainage is perfect.  If it takes longer than a few hours you should alter the soil or grow Citrus instead. 

In my own garden the soil is quite compacted and puddles can sit for days.  I brought in 1/2 cubic yard (13.5 cubic feet) of sandy loam (fill soil) and created a volcano-shaped mound about 8 feet across and 1.5 feet tall at the center.  I mixed some of the soil at the base of the mound with the native soil so there wouldn't be a sharp change in soil texture.  A tree planted within this mound starts out with all of its roots above ground level insuring good drainage.  I have 3 trees planted this way since last May that are looking quite good and have easily tripled the size of their canopies.  I also have one that was planted 15 years ago that has leveled off at about 15' tall and wide. 

As an alternative, you can bring in 13.5 cubic feet of pure sand (masonry or plaster grade) and mix it with you native soil about 1:1 and create a similar mound. 

Do not incorporate compost into the soil.  Compost is very capable of causing anaerobic conditions (perfect for rot disease) when the soil is saturated from rain in winter.  Avocado trees love the ground to be covered with a thick layer of fallen leaves, but make certain they remain on the surface. 

The most important factor in your success is the source of the tree.  The majority of Avocado trees available at retail stores will die or grow poorly.  Growers of "retail" Avocado trees often create a beautiful product for the sales floor, but rarely thrive unless the homeowner can provide perfect conditions.  In my home garden I have planted at least 10 "retail" trees and although many have had some fruit, none have really thrived or ever reached a mature size.  With most of these I would eventually give up and remove after wasting at least 5 years. 

A few decades ago I discovered Brokaw Nursery (wholesale), a famous supplier of orchard trees.  Brokaw was the neighbor of Rudolph Hass (who found his namesake Avocado cultivar) and introduced the Hass to the industry.  Brokaw has not only been the leader in promoting Avocado varieties, they have developed the technique (in conjunction with UC scientists) of producing trees on cloned, disease-resistant rootstock. 

Pretty much all retail trees are grafted on "seedling" rootstock.  This was also true of orchard trees more than a generation ago.  The grower plants an Avocado pit and grows a seedling tree.  The cultivar is grafted to the seedling.  Seedling trees are all different genetically; some have better roots than others.  Most are susceptible to root rot diseases. All retail trees are grown in a compost-based growing medium.  This in itself can promote root disease.  

The vast majority of commercial orchard trees being planted today are grafted onto "clonal root resistant" rootstock.  Researchers have gone to older orchards (trees grafted onto seedling rootstock) where root rot disease is present and sometimes find a lone tree that survives and thrives while all its neighbors have succumbed.  This "escape" tree sometimes proves to have genetically superior roots.  The researchers induce the roots to sucker and grow several rootstock trees to test and observe.  They look for rootstocks that not only resist disease, but create trees that are productive, and for our purposes also look good.  (There is a rootstock that produces productive, but ugly, trees.)

The most efficient method of producing Avocado trees on cloned roots is quite interesting.  The grower starts by growing a pit (seedling) in a container.  Because the big pit contains a lot of energy and vigor the seedling is used as a "nurse" plant.  When the seedling is old enough they graft a short branch of the rootstock tree to it.  Let's call the rootstock "Dusa" (one of the best rootstocks currently available).  A constrictive ring is placed at the base of the graft which will eventually sever the seedling roots.  In the meantime the Dusa stem grows vigorously because of the power of its "nurse".  When it reaches about 2 feet tall the entire plant is placed in darkness for several weeks.  This will cause the Dusa stem and foliage to become pale and soft (easier to induce rooting).  A plastic sleeve is placed over the "etiolated" stem and about 15" of it is covered with potting soil.  The potting soil contains a rooting hormone.  This 2-tiered plant is grown under normal lighting while the Dusa stem grows roots.  After growing sufficient roots the "nurse" plant can be cut off and discarded.  This Dusa tree is then grafted to the desired fruit cultivar.  This young tree is grown outdoors in the nursery for a year or two before it is ready to be installed into an orchard.

This method of providing an Avocado tree with clonal rootstock more than doubles the cost of each tree.  However for me it has been the cost of success.  The only Avocado trees that have ever grown significantly in my garden have been on clonal roots.  I have also noted that when compared to Avocado trees on seedling roots, the leaves are larger and greener and the branches are significantly more resistant to sunburning. 

Carmen-Hass (A)  This is the hottest new sport of the popular commercial Hass.  Apparently one tree in a Hass orchard in Mexico started flowering 3 times per year.  A normal Hass blooms once in spring and is harvested the following year from late spring to early fall.  The odd tree, now known as Carmen-Hass, blooms in spring, summer, and fall with corresponding crops.  A mature tree can be harvested pretty much the entire year!  Interestingly, the shape of the fruit is influenced by the bloom period.  Spring bloom creates the typical pear-shaped fruit.  Later blooms create rounded fruit.  Carmen-Hass trees can grow tall and wide if allowed.  This may be the only Avocado tree your garden needs! 

GEM  (A)  This cultivar was bred by Gray Edward Martin of the University of California, who spent most of a lifetime to create the perfect Avocado.  GEM is the daughter of Gwen, another UC introduction.  Gwen was a nearly perfect decendent of Hass that had a nasty tendency to defoliate in winter.  GEM is a Hass-type fruit that is a more consistent, heavy producer, easier to grow, and a natural semi-dwarf.  Harvest late spring to early fall.   

Bacon  (B)  This is a good pollinator for either Carmen or Gem and produces good to excellent tasting fruit January-April.  Bacon is a very consistent, heavy producer.     

Tomatoes 

ANNA RUSSIAN, AUNT RUBY'S GERMAN GREEN, BETTER BOY, BIG BEEF, BIG ZEBRA, BLACK CARBON, BLACK CHERRY, BRANDYWINE RED, COPIA, EARLY GIRL, GRAPE, GREEN ZEBRA, HAWAIIAN, KELLOGG'S BREAKFAST, LEMON BOY,

MARIANNA'S PEACE, MOMOTARO, NEVES AZOREAN RED, PAUL ROBESON, SUGARY, YELLOW PEAR. 

Consistent dry weather and warming nights are now prime for planting tomatoes.   

 

Peppers

Good Selection of hot and mild.

Squash

GREEN ZUCHINNI

Eggplant

JAPANESE LONG

Herbs

Superb selection

Perennial Color

CUPHEA VIENCO BURGUNDY and VIENCO LAVENDER

We shouldn't sell out so quickly this week.

GAILLARDIA YELLOW  

HEBE RASPBERRY RIPPLE

40 years ago Hebe cultivars were one of our most popular plants creating a rounded shrub to 30" tall that bloomed most of the year with brilliant purple or raspberry flowers.  Most died in the late 1970's from a root disease.  We are willing to try again, because the growers at that time, had recently starting growing plants in a compost based soil.    I have a feeling that if Hebe is grown in proper soil it will perform well.   

NEMESIA BLUEBIRD

Nemesia became incredibly popular about 10 years ago for several reasons.  They bloom most of the year, they are very low maintenance, they stay below 1', and they live a long time (5+ years).   

PENSTEMON APPLEBLOSSOM & PHOENIX MIX

Penstemons are among our top perennials.  They are evergreen, bloom spring-fall, tolerant of various soils and irrigation patterns and grow about 2-3' tall.  Expect 3-4 years of great results.

SALVIA MYSTIC SPIRES

SCAEVOLA