Growing Dwarf Apples

Latest Update 4th October 2016.

Espaliered Dwarf Apple Tree
  • In November each year, the fruit on my apple trees are thinned to one apple on each fruiting spur.  This increases the size and quality of the remaining apples at harvest time. 
  • In late summer, the current year's growth is pruned back to 20mm above basal clusters.  Where there is an apple, the new growth above it is removed.  This focuses the  plant's energy on growing its fruit, and later it encourages the plant to develop new fruiting spurs.
  • I don't prune apples in winter except when the initial structure is being fashioned or later changes to the structure are required.
  • I usually get 50 or 60 large healthy apples off my Granny Smith, but the tree has added a lot of new fruiting spurs this year, and I am hoping for a much bigger harvest. 
  • I use horticultural gum to stop the female codling moth climbing up the tree's trunk in spring to mate and lay their eggs in the tree's foliage or on the apples.  I use pest exclusion bags to keep the moth or larvae away from my apples if they manage to get past the glue.
  • Granny Smith apple trees are self fertile, but benefit from a suitable cross pollinating apple tree nearby.   So I have a grown a dwarf Gravenstein apple tree alongside it to encourage cross pollination
Details.
  • Variety:                                                   Granny Smith.  
  • Family Group:                                          Rosaceae. 
  • Garden bed type:                                     Drip line irrigated. 
  • Recommended soil pH:                             5.0 - 6.5.  
  • Plant Spacings (centres):                          2000mm (espalier). 
  • Cross Pollinating Apple Trees:                   (List)
  • Good Companions:                                   Nasturtium, Marjoram, Wallflower, Apple Mint.
  • Climate:                                                  Warm Temperate.
  • Geography:                                              Southern Hemisphere.  
Nutrition.
Growing Conditions:
  • Full sun.   
  • Minimise soil disturbances to maintain a natural soil structure.  
  • Do not allow the soil to dry out. 
Feed the Soil.  
  • Remove accumulated mulch, fallen leaves, dead branches etc, in winter and dispose of them in a thermal compost where the heat will destroy any pests. 
  • Apply a 60mm layer mature compost on top of the soil surrounding the tree, and cover it with a thick layer of fresh straw mulch.  
Growing Instructions  
  • Propagate apples by grafting, budding or layering (read more).  
  • Thin established trees to one fruit per fruiting spur at the end of November.  
  • Prune back to fruiting spurs when leaders stop growing in late summer, and prune the current year’s growth to 20mm above basal clusters.  
  • Cut out any crossed, dead and diseased branches. (see demo).  
  • Sharpen and sterilise your secateurs before cutting into living tissue on any plant.
Harvesting and Storage.
  • Leave the apples on the tree until late autumn.  They are at their sweetest when they begin to show a light yellow blush on their skins.
  • We only have a couple of espaliered dwarf apple trees, so we don't have a lot of surplus fruit to contend with.  
  • We use our Granny Smith apples in pies and preserve our small surplus as pie filler with other fruit like rhubarb or blackberry.   We use a pressure cooker to sterilise the jars and their contents.
Organic Pest Control.
  • Codling moth.
    • Clear all debris from under the tree in winter.  Dispose of the debris by burying it 500mm under soil which is unlikely to be disturbed for some time, or in a thermal compost.
    • Apply masking tape to the trunk of the tree about 100mm above the ground and apply a ring of horticultural glue around the tree on top of the masking tape.  This stops the adult female codling moth from crawling up the tree to mate and lay eggs in spring.
    • The masking tape protects the bark of the tree from the glue, and makes it easy to replace when it becomes covered in dust or dead insects.   
    • Thin the apples in late spring when they have set.  Check them at least twice a week looking for the first “stings,” or tiny mounds of reddish-brown frass (excreta) about 2mm in diameter. 
    • If you scrape the frass away you can see the tiny entry hole where the newly hatched larvae has just entered the fruit. These affected apples need to be removed and placed in sealed black plastic bags.  They should then be cooked in the sun to kill off the larvae.  Don't put the apples in the compost without killing the larvae first.   
    • If codling moth is a problem in your neighbourhood, cover the fruit with net or paper exclusion bags as soon as they develop, but remember to make the back big enough for the growing fruit.  The bags must have an effective sealing system.
    • This is a useful video about codling moths.
    • A monthly foliar spray of aerated compost tea helps control powdery mildew, but if an infestation occurs, spray the affected foliage with an organic fungicide (like Eco-fungicide in Australia).
    • Alternatively, a solution of 1 part cows milk to 9 parts water makes a reasonably effective organic pesticide against powdery mildew.  It needs to be applied early before the fungi gets well established, and frequently to keep it in check.
  • General:
    • Regular applications of aerated compost tea boost the natural defences of apples by colonising the leaf surfaces with beneficial microbes.  They defend the plant against airborne pests and diseases.
    • Similarly, proper soil preparation including regular applications of home made compost boosts the community of beneficial microbes, which defend the tree's roots against plant pathogens.
    • Exclusion netting with a 20% shade factor takes the edge off intense sunlight in hot weather 35-40 deg C. In extreme conditions of high wind and temperatures over 40 deg C, use 75% shadecloth.