In order to go about transitioning a farm to include more perennial plants—from fruit trees to medicinal herbs, berry bushes to hardy edible roots—you need to understand what does well in your environment and what has potential in your market.
You can glean much of this knowledge from resource books, online databases or fellow farmers and friends. Decisions on what exactly to grow, however, must include in-situ (on your land, in your specific soils, environment and context) trials.
Thus, nothing “out there” is ever exactly as it might be “in here.” 
You must trial the ideal designs and plant recommendations for “out there” on your property first. This way you’ll come to understand their potential for production planting and care as well as marketing a new perennial crop. You’ll find this especially true of perennials, with a much higher upfront investment cost than annuals.
So there is inherently much higher risk associated with transitions from annual to perennial agriculture.
One solution for this obstacle? Introduce the concept of index guilds to farms as a low-cost, low-risk, transition-ready process for making good decisions surrounding including perennials on annual farms.
Read more: An ecosystem garden offers tons of benefits to the grower!
What Is an Index Guild?
An index guild is a planting of three or more perennial plants in order to test suitability to the following:
- Your local conditions such as climate, soil, ecology, hardiness and soil preferences
- Each other as good neighbor plants that partition space, resources and allies
- Each other as companions that help to serve different functions (such as fixing nitrogen, providing shade, mining soil nutrients and more) for each other and the guild as a whole
- Symbiosis—biologically evolved relationships with each other (it’s best to research plant symbiosis in advance)
- You as the steward and your community— provision of useful, edible products and ecosystem services like creating a micro-climate
Q: What is Its Purpose?
A: To Spread
The purpose of an index guild is to spread successful plants. Potential plants are brought into the property and planted as a guild. Then successful plants are spread throughout property or into farm or community.
For instance, an old apricot tree on a farm can testify to the longevity of the variety. You can use it for plant material to plant more apricot trees from suckers. Doing this can also highly impact the overall success against disease, and climate conditions like drought. 
Consider the index guild spreading image above. The small 25-square-foot red spot, blue spot and yellow spot represent different index guilds. After some changes and swapping of plants over a few years, you will have succeeded to the point that they are now being propagated into the larger red, blue and yellow areas of this yard to form larger edible ecosystems.
Index Guild Planting
To plant an index guild correctly, you should follow a few key requirements. These guidelines ensure your plantings serve their roles to trial site-suitability.
- Choose plants from different layers of a wild ecosystem—ground covers, bushes, shrubs, trees—to make a proper guild. (see article on guild design, ecosystem design…)
- Plant near your home for easy observation and care. We are not trialing neglect here. If a plant dies, it should do so due to unfitness for the climate or soil. If a plant isn’t delicious, you should be able to look out and observe that no one picks it.
- Plant appropriately (see article on how to plant a tree). Survival and success should trace back to best management practices.
- Protect against rodents appropriately with tree guards and the like.
- Use mulch to create a well-defined area to make the index guild distinct from other plantings.
- Use wooden stakes and metal laser-etched tags to ensure your plant data is safe. Survival and success of a plant may take years, and your memory won’t serve—especially if you plant more than a few plants in more than a few index guilds.
- Use a spreadsheet to organize your plant data. On our farm, we assign plant ID numbers, listed on metal tags, to make sure each plant has a unique identifier number.
Next time, we’ll look at practical ways to use an index guild, maintenance tips and real-world examples of success.
