Useful plants for chopping and trapping in a forest garden
Chopping and dropping certain plants within a forest garden plan can improve the soil, increase or maintain fertility, and increase the overall yield of the system.In this article I am going to introduce some of the plants that I find most useful as “chop and drop” plants in such a system. These are examples from both my own forest gardens and other forest garden designs that I have worked on.
What does it mean to hack and drop?
First off, if you are new to the concept, hacking and dumping is exactly what it sounds like. Organic material is simply chopped off and laid as mulch around nearby plants – most often around a fruit tree in a fruit tree guild or a forest garden – but also in other garden systems.
The plants you chop and drop are good at gathering certain plant nutrients – often nitrogen, but also potassium and other nutrients to keep your plants healthy. When you chop material from these plants and put it on the surface of the soil, the nutrients it contains will slowly break down and release those nutrients back into the soil where they will eventually be available for other plants in the area to take in.
Some chop-and-drop plants are nitrogen fixators that work with bacteria in root rhizomes to take up atmospheric nitrogen. Others may be particularly deeply rooted, absorb certain nutrients particularly well, or simply quickly generate a large amount of biomass that can be useful as mulch in your garden.
Trees to be felled and felled in a forest garden
Trees can of course be very important within the overall forest garden design. But the trees in the program shouldn’t be considered just for their edible yield. Trees can also be very important as pioneer plants to establish the system, and also as coppice or hoe and fall plants within the system.
My top picks for forest garden locations in a number of different climates and conditions are:
- Alder ssp.
- Black locust
- Siberian pea tree
Of course, these aren’t the only trees that produce biomass that can be used to nourish the soil and improve fertility if the material is chopped and dumped and laid out as mulch throughout the system.
Shrubs for chopping and dropping in a woodland garden
In my climate and the conditions in which I garden, shrubs are important fixers of nitrogen. I use Elaeagnus spp. E. multiflora and E. umbellata. (Note, however, that these can be invasive in some areas.) Some shrubs that are particularly suitable for high-nitrogen mulch are:
- Amorpha fruticosa
- Sea buckthorns
- Elaeagnus spp.
- Myrica cerifera
- Shepherdia spp.
It is a good idea to include nitrogen-fixing shrubs in a forest garden design.
Top perennials to cut and drop
Nitrogen-fixing plants are also found in the herbaceous layers of a forest garden. Some particularly useful nitrogen fixers for these lower layers of a forest garden are:
- Lathyrus latifolius
- Wood vetch (and other sweet peas)
However, it’s also important to note that nitrogen isn’t the only plant nutrient that can be replenished by chopping and dropping. In forest gardens and fruit tree guilds, it can also be useful to hack and drop dynamic accumulators, which are good at accumulating other macro and micronutrients for good plant health.
Comfrey is one of the most famous dynamic accumulators, and I am indeed seeing great results when I use comfrey extensively as a mulch in my yard. But comfrey is certainly not the only plant that can be useful in this way. Other herbaceous perennials that I want to chop and drop in addition to the above are:
- Jerusalem artichokes, cardoons, sunchokes
- Rumex ssp.
Annuals to hack and drop
Finally, I also allow annuals to self-sow. These can also be chopped, discarded and used as mulch in the forest garden. Some of the most useful annuals to hack and drop include:
- Amaranthus spp.
- Chenopodium album
While the plants listed above are of course just a few examples, they may help you plan and plant for long-term fertility in your forest garden.