If you are new to growing apples in a warm and humid climate or you are having troubles getting an apple to begin bearing fruit, we have one technique to getting it to fruit. At a minimum this trick can be used as an indicator to tell us whether or not the plant is even ready to fruit.
There is a belief that chill hours are what is required to get an apple to fruit. As background, chill hours are the number of hours an area receives sub-45 degree temperatures over the course of a winter season. It is believed that each variety of apple has a chill hour number that causes it to begin production of fruit.
Nature is not so simple to follow a simple numerical concept.
The truth is that apples need a specific physical and observable condition to be the case in order to fruit. How exactly it happens, depends upon numerous things, but some are within human control.
The Branches Must Be Horizontal
In order, for an apple to fruit, it has to have horizontal branches. As far as we know there are no studies that specifically say what angle makes horizontal, but it is very clear that apples produce fruit when their branches contain growth other than vertical growth.
Vigorous growing varieties of apples located in the Southeast or the Tropics want to go completely vertical. These apples often look a lot like pears which even more so want to grow vertical in their early years. The key is these trees need branches that are horizontal to fruit.
If there is minimal if any horizontal branching occurring, you can be fairly sure there will be little to no fruit.
Four Reasons that Branches Might Become Horizontal
It Has Fruit On It, Or Did Previously
The most obvious of them all is saved for the first spot. We did this so as you read you can think about this extremely important fact that horizontal limbs = fruit. If you have ever seen a plant with fruit all over it, you will notice just how bent the branches are. The weight of the fruit alone will bend branches. The younger the branch the more pliable it is, and the more it is going to bend.
If you see horizontal limbs, you can guess (accurately) that there was fruit on it before.
You Can (and Should) Bend Them
This technique is by far the most reliable and useful technique for growing apples. We included this at the top so that this message is loud and clear. There are many different ways to bend branches but just by shaping the limbs so that they are either horizontal, or even below horizontal will cause the plant to begin preparing to put on fruit.
Ultimately we are mimicking what we want the plant to do, which is produce fruit which, through the power of gravity, bends branches.
While we will never state the following as a guarantee, over at Bonnie Blue Farms we planted 10 varieties of apples that had been freshly grafted. In order to make an apple hedge, within the first year we bent the trunk of every single tree, which were no taller than 3 foot tall.
To our surprise every single apple fruited that first year.
While these fruits did not have a base large enough to supply it with enough nutrients to make it a good fruit, the fruit made it long enough for the seeds to be viable, which we promptly saved.
This technique is what Kevin Hauser is using in the Tropics of Africa where without bending apples will continue to grow up vertically and never produce. Kevin found that once they started bending branches the apples began producing quite well.
Shade Can Cause Them to Reach
Shade can also cause a plant to have horizontal branches. It can be observed in nature that many fruits will live on the edge of a forest. These edges species will begin to be shaded out by the forest on one side but will still have an open sunny side as well. It can be seen that the plant begins to chase the available sunlight which will cause it to reach out for the available sunlight.
This process will cause bent branches followed by fruiting. Many species such as the native Southeast crabapple (Malus angustifolia) will help promote the creation of forest by fruiting, dropping its fruit a little further out, and as the forest grows up behind it will continue the cycle.
This widely observable phenomena can be seen by many fruiting species of plants.
Natural Physics Can Encourage Branching
The natural world can and does bombard apples with many different types of physical effects. How exactly these all interplay is still a complete mystery. The most commonly studied physics would be the effects of cold on apples. The more northern latitudes can be better suited for large scale boom/bust industrial agriculture because their cycles of cold and light create compact flowering and fruiting making it easy to harvest everything at one time and move on.
How exactly these physics cause branches to be bent is not very clear, but it is clear that without them, and without intervention, branches will not bend, and fruit will not occur.
This is likely where the idea of chill hour comes into play, and that each tree is slightly different to this. But let’s not forget that plants will attempt to adapt to where they live and can change dramatically over time.
So Why Horizontal Branches
Now that we understand how we can get what we want, understanding a bit more of the “why it works” is in order. In order to understand why the branches must be horizontal and why we should intervene if they are not, we must look at how plants survive. In an ever changing world, full of moving objects and physical energies that move throughout a landscape plants are at the mercy of the physical world.
Plants cannot move, and must survive using physiological changes alone.
While some plants can move through sending up root suckers, (apples in general are not those types), plants adapt by responding to the environment with hormonal changes. When certain hormones are being produced by the tree it responds differently. Instead of attempting to grow taller, it will try to fruit more.
Early on many fruits are trying to race to become larger so they are more durable to physical abuses but also able to capture enough sunlight. Changes in the environment will then send signals to the plant that it needs to change course, which causes its hormones to change. These signals are not usually due to a single physical change (such as cold) but due to a whole host of complicated environmental factors such as changes in light, water, temperature, and humidity and when they occur within the lifespan of the plant. All of these in combination cause the first fruiting event, which will then being weighing down limbs with fruit.
A horizontal branch is the key indicator of a plant that is producing fruit. There is no other indicator that really exemplifies this and we can use this to our advantage. The one technique to getting an apple to fruit is quite simple, help it out and bend its branches.