We established a cladode load and thinning time that maximized fruit a
nd flesh size in 'Gialla' cactus pear (Opuntia ficus-indica Mill.). Fi
ve weeks after spring flush removal, second flush flower buds were thi
nned to nine, six, or three per cladode; the same treatment was repeat
ed during the early stages of fruit development. Control cladodes had
a natural load of 15 fruit. Time of thinning did not affect fruit grow
th and ultimate weight. Fruit and flesh weight increased with thinning
, but export weight was obtained only in cladodes with no more than si
x fruit. Heavier thinning did not result in any further increase of fr
uit or flesh weight. Percent flesh was not affected by thinning. Fruit
characteristics, such as total soluble solids concentration and seed
content did not change with thinning, but the seeds : flesh ratio decr
eased with thinning. Fruit on cladodes with the lowest load ripened ea
rlier than those on more heavily yielding cladodes.