So there is something that Christine and I have been working on for awhile and that is our up coming food hedge, commonly called a fedge. Effectively this is creating a hedge, but using usable and edible species of plants to accomplish that goal.
Selecting the species
The question that you have to ask is “what is this hedge’s purpose beyond providing food”? This single question will significantly change the species and density of how one puts together a food hedge. I personally believe that the function comes before the food, where the food is a really good added bonus. Species selection and placement will dramatically change how you have access to pick the foods that you are planting. An apple tree tucked inside of dense brambles and spiny Hawthorns would guarantee you would never pick those apples.
If one wanted privacy and a sincere physical barrier plants would be put together much closer and brambles (blackberry/raspberry) could be used to really tighten up the gaps. Also If desired one could use Trifoliate orange, Seaberry (Hippophae rhamnoides), or a heavily pruned Hawthorn like Mayhaw (Crataegus aestivalis) to provide a physical deterrent.
To make a hedge more private evergreen varieties can be picked. Now this is where my northern neighbors will have a much more difficult time than my sub-tropical and very southern ones. In general I think the majority of evergreen fruiting plants are warm loving sub-tropical varieties. The evergreen of the north tends to be Pine trees and things like cedars. Since these species are evergreen they will eventually fill out they will provide the best visual barrier. Some varieties to be considered are: Very Southern Blueberries, Blackberry, Avocados, Citrus, Pineapple Guava Acca Feijoa, and bananas. Here is a link Evergreen Fruit Trees for Hedges I found that has some varieties I haven’t mentioned. Note: Some are quite sub-tropical species, although there are some more cold hardy things in there like the Guava types.
Orientation is important
Orientation is obviously extremely important anytime your stacking and layering plants. The smallest warmest loving plants should be the most southerly (for Northern hemisphere), while the coldest, or tallest varieties in the most Northern location. I find that one of the best edge plants in the shady, northern spots are bramble plants like blackberries and dewberries.
There is another thing to consider with orientation. And that is wind directions. One of the most important things that a hedge is used for is to block and divert winds. For the Gulf region our predominate winds come from the South East, while supposedly most other places in North America its North West (I think). Why is this important from a species perspective? If you are putting very wind sensitive plants as your most frontal defense against winds “you’re gonna have a bad time”. This is precisely one reason why we have decided to go with bamboo as our front most species instead of going full on food forest. We have some serious winds around here, and putting hundreds of dollars into blueberries and avocados doesn’t makes sense if they get blasted to bits by winds.
One thing that people may not consider when building their hedge is dwarfing trees so that they become much bushier. If you prune a tree’s sides, it grows taller, if you cut it off at the top, it grows outward. This means that we can use this to our advantage. In my case I am building a privacy food hedge on my southern most boundary of my property. It just so happens that my garden is right north of it. I absolutely cannot have trees like how they are right now at about 40 feet tall. Therefore I am going to select varieties and dwarf the varieties I plant down to around 15 maybe 20 foot tall. That way it doesn’t shade my garden particularly in the winter time.
Steps for Design
Using a sets for design and thinking is the one thing about permaculture that isn’t taught or spoken about enough. Permaculture is actually more of an analytical concept than one about food forests or rocket mass heaters. You should use methods of analysis to reduce what you have to think about therefore reducing complexity and focusing thought. Believe it or not this is really the same skill necessary in all analysis, but that’s worth saving for another time.
I have started to show some of the steps one needs to look at. Function. Deciding exactly what the function of the hedge will be will start to limit choices and design so that one can focus on the next steps. Another thing that I use is measuring out the area and considering the largest plants first, followed by the smallest. The smallest ones can be added overtime, but the largest ones really dictate what other species can be there, and how the overall look will work.
It tends to be the case that analytical design works from the most broad and largest down to the smallest. Seems like a no duh, however, be careful because you might catch yourself worrying about the varieties of blueberries you need when you haven’t even decided what the main large trees are going to be. That is a big mistake. I personally choose the overall height of the system, define the number of layers that will exist (not vertical but over the area), I then select the overall heights of the layers, select species that can fit those heights (and also roles), and finally start choosing specific varieties.
Hopefully this helps some thinking about building food hedges and hedges in general. If I can finally get caught up on things we have going on around here, I might actually post some basic basic designs that I’ve done.