The Avocado and Mango on the Sand Lands 
of Palm Beach and St. Lucie Counties 
John B. Beach, West Palm Beach 
Mango and Avocado trees seem to 
thrive well on the sandy soils along the 
coast in Palm Beach and St. Lucie coun¬ 
ties, as evidenced by many old Avocado 
trees six to eight feet in circumference, 
and 40 to 50 feet in height, and by Man¬ 
gos less lofty, but running larger in girth. 
The soils, where almost all of these old 
trees are found, are classified by the U. 
S. Soil Survey as various grades of St. 
Lucie sand, Palm Beach sand, and 
Gainesville sand. Nine-tenths of them 
are on the former, owing mainly to the 
fact that this alone has proven suitable 
for pineapple growing, and this was for 
many years the only form of agriculture 
in this region; all the dooryard trees were 
planted in it. The Palm Beach sand em¬ 
braces what is locally known as “beach 
hammock,” and lies on the ocean side. It 
consists of a good percentage of calcar¬ 
eous material, largely organic, with hu¬ 
mus, mingled with silicious sand. The 
Gainesville sand is confined in this sec¬ 
tion to the so-called “red hammock,” un¬ 
derlaid with rock, only occurring on the 
eastern shores of Lake Worth and Jupiter 
Island. 
On Palm Beach sand the Mango does 
not seem to thrive so well, bears poorly, 
and is often troubled with a fungus 
blight. Avocados, however, thrive, and 
make huge, productive trees. Where 
found on the Gainesville sand, both trees 
seem vigorous and productive, although 
there is sometimes a tendency to blight 
among the Mangos. Of the St. Lucie 
sand areas, that described as the “yellow 
sub-soil phase,” where yellow or orange 
sub-soil appears near the surface, is the 
best for both trees, as is the case with al¬ 
most anything else planted, either trees, 
pineapples or vegetables. However, lit¬ 
tle of the famous Pineapple Ridge in St. 
Lucie county has this sub-soil. 
The other determining factor is the 
humus content. St. Lucie sand is de¬ 
scribed as pure silica, with nothing else 
but humus. In the absence of the yellow 
sub-soil phase, all depends on the per¬ 
centage of humus. Hundreds of acres of 
old pineapple fields, which have been 
abandoned to grow up in Natal grass and 
weeds, and which we all hope will some 
day recover their former productiveness, 
are at present useless as well as unsightly, 
and all would be glad to see them produc¬ 
ing Avocados. Mangos are easier start¬ 
ed, and require very little fertilizer, but 
not being such money-makers, few care 
to plant them. We know from the big, 
old, bearing Avocado trees of the door- 
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