How can you tell if your trees are healthy?

If all is going well with your trees this spring, you should be seeing growth like this on your trees:

New spring growth on an apple tree
New spring growth on an apple tree

This time of year we like (and expect) to see a flush of strong, healthy new growth in our trees, particularly on young trees.

Successful fruit growing is all about helping the tree to balance its energy between growing new wood (i.e., new shoots, as you can see in this photo of a young apple tree) and growing fruit. If it grows too much of one, it tends not to grow much of the other.

We need the new wood so the tree continually has new buds being formed to produce next year’s fruit (though the buds can also form on older wood in some trees).

But we don’t want the tree to put too much energy into growing wood at the expense of putting its energy into growing fruit – it’s a balancing act.

Shoot length is one of the best indicators of the overall health of your tree, and spring is the time to monitor it – so visit your trees and have a look.

If you see plenty of young vigorous shoots (anything from a few cm to 1 metre long, depending on the type and age of the tree), you know the tree’s pretty happy.

And if you’ve done a great job with your pruning, you’ll also notice that the new shoots are growing in the right place in the tree to make future fruit picking easy and manageable.

Here’s what healthy spring growth looks like in cherries:

On a young plum tree…

Healthy spring growth on two year old plum tree
Healthy spring growth on two year old plum tree

On a mature plum tree…

An Angelina plum tree showing vigorous spring growth
An Angelina plum tree showing vigorous spring growth

and finally, a mature apricot tree that’s growing beautifully (note the beautiful red colour of the fresh new growth, which will gradually fade through orange to green).

Beautiful new growth on a mature apricot tree
Beautiful new growth on a mature apricot tree

Thinning cherries … or not?

As part of our continuing series about fruit thinning, this week we’ll have a look at cherries, because we’re often asked if they also need thinning.

Tiny cherries in spring
Tiny cherries in spring

In fact, we recommend thinning all deciduous fruit (well, all the types we grow anyway) except for cherries.

In non-organic orchards, most thinning is done with chemicals, but in organic orchards and gardens we do it all by hand.

One of the most exciting parts of spring is actually at the end of the blossom period. It’s not always possible to tell just from how many flowers your tree has how big the crop will be.

Watching the flowers dry up and fall off your trees reveals the tiny fruit underneath, and it’s only then that you can really start to assess how big (or small) your crop will be.

Cherry flowers falling off to reveal the tiny cherries underneath
Cherry flowers falling off to reveal the tiny cherries underneath

Cherries usually have a pretty good crop most years – they are not as likely to have a heavy crop one year followed by a light crop the year after (which is called biennial bearing).

Plus, they grow on nice long stems, so don’t crowd each other out. It’s also pretty unusual to see branches or laterals in cherry trees breaking from the weight of bearing too much fruit.

In fact, most of the reasons we thin other fruit doesn’t apply to cherries, so that’s one job we don’t have to do!

Thinning to protect your tree

As part of our continuing series about fruit thinning (a very relevant topic in spring) this week we’ll talk about the second main reason we do thinning, which is to protect the structure of our trees.

A broken lateral in an apricot tree caused by to much fruit (or not enough thinning)
A broken lateral in an apricot tree caused by to much fruit (or not enough thinning)

Most fruit is carried on the small side shoots, or laterals, that grow from the main branches — they are a very precious part of the tree, and need to be protected. Left to its own devices, the tree will frequently set so much fruit on a branch or lateral that the weight of the fruit breaks the branch, as you can see in the photos above and below.

Too much weight has broken branches in this apple tree
Too much weight has broken branches in this apple tree

Our job when thinning is to remove some of the fruit that the tree has set, leaving only as much as any structural part of the tree can easily carry.

Bebeco apricots after thinining - not too much weight for the lateral to carry
Bebeco apricots after thinining – not too much weight for the lateral to carry

It’s important to imagine how large and heavy the fruit will be when it’s fully mature – as a very rough rule of thumb, a short lateral can only bear the weight of one piece of fruit, and a longer or stronger lateral can carry two or more pieces.

Tatura 211 peach after thinning - just one peach on the lateral
Tatura 211 peach after thinning – just one peach on the lateral

Of course the actual amount of fruit you can leave on the tree depends on many variables:

  • the type of fruit,
  • the variety (cultivar),
  • the ultimate size of the fruit at harvest,
  • whether the tree is heavy, medium or light crop,
  • when it’s due to be harvested,
  • age of the tree, etc.

It’s fine to just follow the rule-of-thumb guidelines we provide, or if you’re keen to protect your tree and in a hurry to get good results you can use the charts we’ve developed in the Grow Great Fruit program and the Fruit Tree Thinning short course to save yourself a few years of trial and error!