There’s been a lot of un-learning happening in my garden. I learned to not do a lot of things I was doing.
The good news of all this upheaval is most of these learnings add up to less work in the balance of thing and more diversity in the soil and species in my garden. The goal in all of them is creating an environment that is as self-sufficient as possible.
Stop amending planting holes
From Linda Chalker-Scott, an associate professor of Washington State University, I learned two crucial planting techniques.
The first was a new (to me) way of planting nursery-bought plants. Chalker-Scott says that when water hits any new medium, going from one soil texture to another, it slows or stops.
Better to have one medium, your garden soil, throughout the root zone. So that means shake or rinse off the nursery soil, using garden soil in the hole.
Amend around the crown only with nursery soil, fertilizer or amendments that will trickle down via watering and worms.
Here are the details: https://s3.wp.wsu.edu/uploads/sites/403/2015/03/soil-amendments.pdf.
The old wisdom of planting was basically: dig hole, plunk in plant as-is and add compost or fertilizer to hole.
When you keep the plant in the nursery soil, the plant, which adapted those cushy conditions, will often stay within that original shape without sending roots out to acclimate to the existing garden soil. It eventually fills that space and starves or drowns just as if it was an overgrown plant in a tiny pot.
It’s heart-rending to pull out a sad plant after a season and see a wimpy root ball that never got wider than the original quart-size pot.
I began applying Chalker-Scott’s method and noticed new plants were establishing much faster, even in areas with challenging soil conditions.
So now I dig the hole as deep as the root ball and twice and wide, putting the garden soil to the side. I water the hole and the new plant. I shake off the fertilizer-filled nursery soil into another pile (some go as far as to rinse it off entirely). If roots are circling, I loosen the root ball with my hands — or in dire cases, my hori-hori knife — and replace garden soil around the plant. Then I top-dress with nursery soil and/or compost or any desired fertilizer.
Don’t line containers with gravel
Many people believe a layer of gravel at the bottom of a pot will “improve drainage” even if there is no hole in the pot, thinking excess water will collect in the gravel and save the plant roots from drowning. Chalker-Scott did a simple presentation at the Northwest Flower and Garden Show a few years ago that blew my mind.
I have been warning nursery customers off using gravel, Styrofoam, bits of clay ever since.
You can try the demonstration yourself: Take a clear plastic cup or glass, line with a layer of gravel topped with soil. Pour in water. The water will hit the gravel and retreat to the soil level.
If there were a plant in there, the water would be pooling around the roots — exactly where you don’t want it.
The reason? It goes back to the idea of water slowing down with each change in soil texture. It hits the gravel, says “nope” and heads back up. You can learn the specifics here: https://s3.wp.wsu.edu/uploads/sites/403/2015/03/container-drainage.pdf.
Stop pulling weeds
This is a tough one. Pulling weeds is so satisfying — both physically and mentally. You feel so virtuous as the soil releases the offending root into your grip — gotcha! However, every time you pull out a plant — whether a dandelion, a cover crop of alfalfa or a spent tomato plant — it wreaks havoc with the bacterial web in the soil, which is the garden’s life support. Also, pulling weeds (or tilling soil, for that matter) can bring buried weed seeds into the light, adding to the problem.
The better way to go, experts say, is to cut weeds to the ground — repeatedly if necessary — and smother with a competitive ground cover or bark chips. I can hear you — but what about the insanely vigorous plants that grow twice with each cut?
This fall I was interviewing eco-friendly landscapers to help clear an area riddled with Trollius (buttercup) and bindweed, and they all agreed — cut and smother, and potentially repeat. If you missed some, cut off the flowers before they can go to seed, and selectively water desirable plants instead of the weeds if possible.
Stop cleaning up, and leave the leaves
Say goodbye to “fall clean-up” as you know it. You may have seen the “leave the leaves” campaign in fall on social media.
All that obsessive raking and bagging of fallen leaves and dried perennial stems takes away wildlife winter food sources, shelter and nesting sites and nutrients for your soil.
Happier and easier alternatives are to mow over your leaf pile (if it’s thick heavy oak leaves, say) and add as a shredded nutritious mulch that warms your plant’s roots while feeding them, compost them or just leave them, depending on your tolerance for wildness.
Even dead trees left upright, also called snags, can be a benefit to birds and other wildlife over the winter. The Bellevue Botanical Garden’s Native Discovery Garden has several large snags giving shelter to fungi, birds, insects and animals.
Ultimately, your easiest, happiest garden will come from choosing plants that want to grow where you put them, rather than creating false bubbles for them to live in temporarily. (That’s what containers and greenhouses are for.)