Willamette Valley, Oregon, Zone 8b
When can I prep my garden beds?
March-ish. Look for these conditions:
- Air temperature is consistently over 55 degrees, so our native insects such as mason bees will have had a chance to come out of hibernation.
- After several dry days. If the soil is too wet, prepping your beds will be more work and damaging to your soil structure.
OK Let’s Get to Work!
- Chop and drop any leftover cover-crop. Cover crop breaks down quickly. (A week or so in warm weather.)
- After you’ve given your cover-crop a minute to break down, remove all the leftover winterizing mulch from your beds. I toss it all in the compost.
- Refill raised bed boxes. Garden boxes looking empty? That’s because raised beds usually have a high percentage of organic matter which breaks down. (Soil, which is technically sand/silt/clay, does not break down.) Although it’s best to refill your boxes the fall, the second best time is now. Fill with a garden blend that has sand/silt/clay as well as organic matter rather than straight compost. Overusing compost (we only need 3-5 percent organic matter) leads to a build-up of phosphorus and other nutrients in the soil. See this OSU Extension article. Gently blend the new soil with a digging fork to avoid creating a separate soil horizon.
- Pro-tip: It’s difficult to buy garden soil in the Willamette Valley with clay in it, (because our native soil has so much!) but clay is very beneficial to your garden boxes because of the cation exchange process. Check out this super-cute educational video that explains Cation Exchange . Keep this in mind as you’re digging earthen works in your soil wondering what to do with our heavy clay. (Perhaps a small pile somewhere that can be sifted in from time-to-time?)
- Slug Control: Set beer traps for the slugs (pill bugs like these too). At least one per bed. Keep the traps a little above ground level to protect ground beetles. I also sparingly sprinkle Sluggo for the slugs that don’t get drunk enough to fall in. Copper tape is also effective at keeping slugs out of your beds and pots. See my Slug IPM for more information.
- Nutrient Amendments: At this time also add any organic nitrogen amendments. I use organic feather meal which is nitrogen rich with an NPK of 12-0-0. A well balanced fertilizer has all three NPK nutrients, but since I have such high amounts of organic matter, I’m only lacking the N. (See my Soil Test Results.) I sprinkle according to the recommendations and lightly rake into the soil. I prefer organic fertilizers since they break down slower reducing the danger of burning the plants. In general, organics are safer for us and the environment. I use Down to Earth Organics because they are reasonably priced, organic, and produced locally in Eugene, Oregon. For my in ground beds that have much less organic matter, I use a well balanced fertilizer, like 4-4-4.
- Stab and wiggle. Channeling Poseidon, I pull out my digging fork and spear the ground. Then I wiggle the fork in all directions and gently lift the soil. This loosens and aerates the soil without destroying the structure.
- Lightly work the top inch or so of soil with a scuffle hoe.
- If you have in-ground beds (i.e. a lot of clay), a top dressing of compost will help to dry things out and add organic matter to your soil. If you have a raised bed box, it’s likely that there is already a lot of organic matter in there already.
- Leave your soil exposed for now. This will help the soil to warm up. You want to see at least 40 degrees for cool tolerant crops and 50+ for warm season crops. This will also allow the soil to dry out and give you time to get the slug hoards under control.
But when do I turn the soil?
Another of the four soil health principles is, “Do Not Disturb”. Turning your beds destroys the soil structure essentially demolishing the microbial apartment complex. This demolition releases a flush of nitrogen, but otherwise is detrimental to the overall health of your soil. The surviving microbes will go to work rebuilding the structure, but I prefer to leave their homes intact whenever possible. The only tilling I do is when I’m establishing a new planting area in a hurry. I prefer to establish new beds by sheet mulching in the fall. Besides, tilling is backbreaking. I haven’t done it in years and have not missed it a bit.
Chicken Tractor 🐔💚
If you have a flock of chickens, now is a wonderful time to employ a chicken tractor. This is a moveable cage or pen to confine your hens to a specific area. Chickens scratch the soil, eat the decomposer bugs, and deposit nitrogen rich fertilizer. Then they pay you for the privilege with eggs. This is a permaculture function-stacking dream right there.
For an 8’ x 4’ bed, three chickens for one week will adequately prep your beds for the growing season. When they’re done, rake the bed and allow it to cool for a couple weeks before planting. We did this at our school garden with chickens on loan from Millennial Acres and had a fantastic growing season without a lot of extra soil inputs.
Stale Seedbed Method of Weed Control:
- Prep your bed several weeks before you wish to plant.
- Keep soil moist (our usual rain does this) to coaxes the weed seeds to germinate.
- Scuffle hoe them down. This also churns up new weed seeds.
- Let them germinate then scuffle hoe them down again.
That’s all there is to it. Now you should be able to plant in your beds without nearly as much weed pressure.