Nature's colourful display bears fruit
You can give your trees a helping hand to provide a fine crop, writes Gerry Daly
It has been estimated that only 1pc of fruit tree blossom is needed for a good crop of fruit on fruit trees such as apple, pears and plums. It might seem wasteful of resources for a tree to make a hundred times as many flowers as it needs, but the tree does not know which blossoms will be visited by a pollen-carrying bee and which ones will fall unfertilised.
Better not to leave it to chance. Hence the big show of flowers that can be seen from a distance by bees, which have relatively primitive eyesight.
If every apple, pear or plum flower were pollinated, the tree would not have a hope of ripening them all.
Soon after flowering, all unpollinated flowers are shed as worthless.
The remaining fruitlets have set at least one seed, and often up to 10 seeds in apples and pears, and one stone in plums. These seeds, by hormones, control continued fruit development.
Having tasty sweet fruits is a very effective way to ensure that tree seeds are carried away from the parent trees to be dropped in new areas. It has been so successful that humans have carried these fruits all over the globe, starting from their original region in the Caucasus.
So, for the tree, there is no point in putting resources into seedless fruits. So it sheds them because often it is carrying much too big a crop, much more than it can swell and bring to ripeness.
Around now, until mid-July, the 'June drop' occurs when fruit with low seed counts are jettisoned.
The tree has only limited resources and if it can drop half of its developing fruit load, the resources of sugar and nutrients going to the remaining fruits are doubled.
This greatly improves the quality, size and flavour of the final crop.
Unfortunately, though, sometimes a fruit tree drops all of its fruit load. Perhaps the fruit was not properly pollinated, or the tree is growing in unsuitable conditions and is struggling to grow, let alone produce a crop of fruit. Poor conditions could be poor soil, shade, dry soil or competition from trees.
Fruit trees do not always drop enough fruit, carrying too great a crop to ripen well. The result is large numbers of small, tasteless, poorly coloured fruit.
It is worthwhile, when the natural drop has occurred, to do some thinning by hand. This gives nature a nudge in the right direction and can greatly improve the quality of a crop.
Fruit thinning might look a bit daunting, but it is surprising how quickly it can be done. Thinning is done by pulling off, or pushing off, some of the remaining fruit, sometimes taking off more than is left.
The fruit stems can also be snipped away with secateurs. A good rule of thumb to use is that for each apple or pear fruit left, there should be 10 to 15 centimetres of branch. So, a 60 centimetre branch can have four to six fruits.
Ideally these should be evenly spaced but they can be grouped to some degree. Plums should have five centimetres of branch on average.
Another good reason for thinning is to combat the condition known as biennial bearing - when a tree is laden one year, but so weakened by the effort, that its resources for fruit setting the following year are used up.
No fruit, or very little is set, and a pattern of cropping every second year develops.
Thinning fairly hard in the 'on' year helps to even out cropping.
For plums, heavily laden branches are likely to break, if not thinned, losing fruit and allowing the entry of fungal diseases.
MAKING SENSE AT HILTON PARK - n Sense and Sensibility finds the perfect home for its summer stage production on the lawn at Hilton Park in Co Monaghan. While the house dates back to 1734, a little before Jane Austen's time, it does have a long history of involvement in cultural events, including hosting the much loved and now defunct Flatlake Festival. Tickets: hiltonpark.ie
PICK OF THE BUNCH - African daisy, or osteospermum, pictured below, is a great old stalwart of gardens in the milder areas of the country at this time of year. It is native to South Africa and not completely hardy but survives well in places not too far from the coast. Its swathes of glistening white, purple-backed, daisy flowers are a joyous delight.
Know YOUR ERAS - For those rainy summer days, a plant lovers history through the ages, The Story of the English Garden, from the National Trust, beautifully illustrated, with everything from glasshouses to outdoor rooms. Out June 28, £17.72