Quote:It is possible to grow large Royal Gala fruit only on large caliber fruiting wood.

Growing Large Royal Gala

John Wilton
Deciduous Fruits Specialist
AgFirst Consultants Hawke’s Bay Ltd.
New Zealand

Reprinted fromThe Orchardist1997 70(5):13-15.

With harvest over, it is time to scrutinize the results we obtained from the 1996/97 crop.Small
fruit size has been a major feature of this year ’s crop and will have knocked the cream off grower
returns.

Pricing signals over the years show us that to be in the money with this variety we need to be
growing a large proportion of the crop in the 110 and larger fruit size counts.This means having
mean fruit size of around 115 and certainly no smaller than 120.In fact, going on the 1996
returns there is a difference in return of around NZ$3.50 (one $NZ equals approximately
$US .53) per carton between a crop averaging 115 and one averaging 130.If you can shift the
size up to near 100 count then you can lift your average return by a further $3.50 per carton.
Undoubtedly some yield will be shed in shifting size up to the 100 count range, but you have to
consider the effect harvesting and packing costs have on your net on the tree return to put the
yield-by-return equation into perspective.

Picking and packing costs for an export carton are about NZ$4.60, excluding packaging
materials.If we take NZ$4.60 off the return to give an on-tree value ready to pick, the 130 count
crop is worth only NZ$7 per export carton whereas the 115 count crop would be worth
NZ$10.50 and the 100 count crop NZ$14 per export carton.Put another way, to match the value
of a 2000 export carton/hectare (809 cartons/acre) crop of 100 count average fruit size, you
would need 2666 cartons/hectare (1079 cartons/acre) export of 115 count and a massive
4000 cartons/hectare (1619 cartons/acre) of export at 130 count average.

Growing large export crops of small Royal Gala apples is great if you want to assist the
government in reducing the unemployment, but is a difficult way to make a living compared to
thinking smart and growing half the crop of large-sized fruit.

Furthermore, from what I have seen of Royal Gala in South Africa and South America, our
competitive advantage with this variety lies in growing it big because they are quite capable of
meeting the market demand for small Royal Gala without our help.

SMALL FRUIT SIZE PROBLEM THIS YEAR
Sure, we have had a difficult growing season this year in regard to fruit sizing and the season
must take some of the blame.Perhaps 20%?Certainly from what I have seen, blaming the
season for more than 30% would be generous.

This was a year when the rewards for getting it right were high compared to a less than adequate
crop husbandry job.

Royal Gala is a naturally small fruited variety which we are trying to grow well above its normal
size range.To grow it big takes considerable skill and leaves little margin for error.All along
the way orchard practices and techniques need to focus on growing large fruit.At each step in
the production cycle, precise management is required.There needs to be careful attention to
detail with every step.Because of the large price differential large fruit size commands, the
rewards for growing it well are high.

FRUITING WOOD SELECTION AT PRUNING IS THE FIRST STEP
It is possible to grow large Royal Gala fruit only on large caliber fruiting wood.With this
variety, it is my opinion that fruit bud quality and the strength of the wood carrying the buds are
more critical than the actual wood age itself.Even lateral buds of 1-year fruit wood will size
well on strong wood greater than 10 mm in diameter.If this were not so, we would not get some
of our best Royal Gala fruit from 3- and 4-year-old trees.

With this variety fruiting wood needs to be pencil thickness or greater in diameter if more than
one or two fruiting buds are to be left on the fruiting lateral.Where growth is weak, or over-
enthusiastic summer pruning has removed much of the better fruiting wood and the choice of
fruit bud is poor, it is necessary to retain weaker fruiting wood to give sufficient fruit bud
numbers to carry a full crop.Where weak wood has to be used to build fruiting site numbers, it
must be shortened down to two to three buds.For good fruit size, Royal Gala needs adequate
leaf to fruit ratios and the position of these leaves must be where they will support fruit
development rather than fuel excessive vegetative growth.Bourse shoot growth which
terminates early in the growing season maximizes fruit sizing potential.By shortening weak
wood to two to three buds it is possible to stimulate these bourse shoots.Stronger fruiting
laterals can carry more buds so should not be pruned back as drastically.Horizontal and pendant
shoots which have good quality fruit bud need only be shortened up to about pencil thickness,
otherwise bourse shoot growth will become excessively strong.Strong, slightly pendant fruiting
laterals produce good quality fruit so long as they are well positioned in regard to sunlight.

As a rule, fruiting laterals with positive gradients should not be shortened until fruit weight pulls
them down to, or beyond, the horizontal.

Shoots and laterals with gradients steeper than about 40º above the horizontal tend to become
excessively strong if left in the tree, so they should be eliminated.Vertical growth, even if only
one year old, arising toward the base of a fruiting lateral tends to shade and rob fruit carried
farther out on the lateral, so it is necessary to prune off this type of wood.

STRIP OUT WEAK WOOD
Much of the small fruit we see in Royal Gala is carried on weak, shaded, fruiting wood close into
the leader or dangling off the lower fruiting arms.Pruning needs to target this wood for ruthless
removal.

Higher up the tree poor fruit size is often seen on lateral buds of weaker 1-year-old shoots found
on the end of horizontal or pendant laterals.Again this type of wood needs ruthless removal
because it is too weak to give adequate leaf to size fruit and does not respond well to chemical
thinning.

LIGHT EXPOSUREABSOLUTELYCRITICAL
Royal Gala shows extreme sensitivity to sunlight.Quality falls off rapidly if the fruiting wood is
shaded.To maintain good light in the lower tree, its shape must be pyramidal in order to let
satisfactory light penetrate to the lower branches where fruit is cheapest to produce.The upper
tree, therefore, needs to be furnished with numerous branches which become progressively
smaller and weaker toward the tree top.The upper tree branches should not be encouraged to
develop massive structure, but kept confined to single unbranched structures furnished largely
with fruit bud.

The lower branches are larger and will need more structure to enable them to develop their full
fruiting canopy potential.At pruning, wood on these lower branches needs to be maintained in a
single plane to avoid within-branch shading.Uprights and weak pendant wood must be
removed.

As well as attending to light requirements, this type of tree assists with pest and disease control
too.By keeping the upper branches young and maintaining high light levels within the tree,
burrknot development is discouraged, thus minimizing mealybug problems.Spray coverage is
easy to achieve and their open nature allows quick drying, ideal for easy apple scab control.

Moderate vigor balance is critical to maintain high light levels throughout the season.Pruning
levels need to be carefully judged so as not to stimulate high vigor.

BIG HEALTHY LEAVES ESSENTIAL
If you are going to grow large Royal Gala, strong healthy leaves are important to supply the
photosynthates necessary to size the fruit.Adequate levels of fertilizer, particularly nitrogen and
potassium, are needed.Royal Gala does not show sensitivity to low calcium-related disorders so
can stand higher levels of potassium than bitter pit prone varieties such as Braeburn or Cox’s
Orange.This means that with Gala we can be a bit more generous with potassium than on
calcium-sensitive varieties.

Pests and diseases which injure leaf quality must be well controlled.Leaf curling midge, mites,
powdery mildew and black spot all have potential to take the shine off Royal Gala returns if they
get a chance.

CROP LOADCRITICAL
Royal Gala is a variety capable of overset so it needs careful thinning management.Crop load
needs to be established early.Appropriate chemical thinning is the main tool for regulating crop
load on this variety once pruning has eliminated weak bud and surplus fruiting sites.

Satisfactorily thinned Royal Gala trees need to look as if there is no crop left 4 to 6 weeks after
flowering for good fruit size by harvest.Adjusting crop level with later hand thinning is usually
necessary unless exceptional results have been achieved with the chemical thinning program.
Careful fruit counting to establish crop load is necessary at hand thinning and the greed factor
put on the back burner.Much of this year’sdisappointing fruit size in Royal Gala was due to
failure to establish a satisfactory fruit load at thinning time.

Crop load also has a profound effect on the time of fruit maturity and amount of fruit color by
harvest.A recent paper in the French journalFruits and Legumesreports a crop loading trial on