Sunlight as a key to plant growth is a fact, either not understood well enough or neglected, probably because of an abundance of sunlight in the tropics. I haven’t discovered any published advise that emphasises this issue. When I drive past large groves being developed, I am struck by two things. One these orchards are invariably mono cultural – mango, amla, guava or coconut or whatever- and their layout seems boringly mechanical. The rows run parallel to the fence and in them stand saplings like soldiers in a parade. If there were undulations in the ground they would have been flattened like, well a parade ground. Alas for armies, as well as plants, flat grounds and geometric patterns are not what they must cope with in the business side of their lives.
It is worth belabouring that everything -and everything- comes from the sun. Food, energy, winds, rain and all other materials are governed by the sun. Ahead of any photo voltaic cell or collector or anything man can invent, trees are the most efficient -and by far, the prettier!- solar energy converters- provided you expose them to sunlight give then moisture to prevent dehydration.
The sun courses from east to west. If planting rows are aligned east-west, they would be uniformly exposed to sunlight. Mono cultural plantations have the dubious merit of all their stock growing at the same rate. In a biodiverse stand that is not so. A fast growing tree can stifle a slow growing one. Proper solar alignment will avoid this.
When I visit fully developed groves, I have been struck by how most of them are entirely shaded. This might be enjoyable if you were visiting on a hot summer day. But when it has rained for days and the trees drip for a few more and the earth beneath your feet squelches, it can be very depressing indeed. I have known cottages and houses in such groves to remain dark and damp throughout the year. I personally like a good percentage of land that will remain open and sunlit throughout the year. That is what made me lay out the five east-west roads that separate the planting blocks.
On either side of these roads, I dream of little cottages that would have a sense of open space and brightness. Behind these cottages and in front, across the road, would be the densely planted blocks. Another advantage of an east-west orientation is that it would enable some intercropping between tree rows.