For the last 3 years my macadamia trees flower but the flowers die and do not produce fruits. I have a about 100 different types of fruit trees in our orchard with a lot pollinators (bees, native and European). The two nut trees are about 9 years old. Will enclose phots. We live in the subtropics.
You should probably do a soil test and consider fertilizing the trees. This article has information on the required pH level of the soil, as well as what the trees need to thrive. I hope this will help.
https://www.gardeningknowhow.com/edible/nut-trees/macadamia/how-to-grow-macadamia-trees.htm
I am looking at spraying Molasses on Macadamia trees as a fertilizer. The reason for this is that I feel that I can spray probably every two to three weeks and end up with a tree in really good health, with plenty of fruit and free of pest. The rate of Molasses to water would be about 0.66% or as guided. Any information on this subject would be most helpful. Many thanks,
It sounds like you know about the benefits of using molasses. Here's some info:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/feeding-plants-with-molasses.htm
I also want to provide you with a link to an article about foliar spraying:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/what-is-foliar-spray.htm
In 2019 my well established (20+ year old) macadamia nut tree was subjected to extreme high heat conditions for about a week. During this time the tree was not watered. All leaves have fallen off the tree. The tree has not yet returned to its former self. There has been no new leaf growth other than some shoots near the base of the trunk. Will my tree return to a normal state? If so, what can I do to help revive it?
I suspect that more is amiss than drought stress. They are susceptible to insects and disease. If you haven't seen leaves since 2019 it may have succumbed. Here is a scratch test you can try. If it is still alive, seek the help of an expert at your local cooperative extension or an arborist.
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-scratch-test.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-leafing-problems.htm
https://www.gardeningknowhow.com/edible/nut-trees/macadamia/how-to-grow-macadamia-trees.htm
http://blogs.ifas.ufl.edu/volusiaco/2018/03/22/macadamia-production-as-an-alternative-crop/