Turning Paved Areas Into Gardens
What do people do when they have a portion of their property taken up with a paved or cemented area.
This is something I have never thought about but came across reading blurbs about in the urban gardening areas.
So naturally I deep dived into it for a night SOOO let me babble about it because it MAKES SO MUCH SENSE TO DO THIS... Pavement was not removed in this + a condensed, note taken approach to this concept.
Build Tall Beds
Crops need room to send roots down into the soil. Providing plenty of room to grow means your crops have a strong foundation, hold moisture longer, and can access more nutrients in the soil through deeper roots. Raised beds on pavement should be a minimum of 24 inches tall and ideally 32 inches tall! Taller is always better, especially if you live somewhere with hot and/or dry summers.
Filling Your Raised Beds
When you build raised beds on the ground, your crops have access to the soil underneath for draining excess water from above and wicking water up from below. Building on pavement takes this away, so how we fill the beds really matters!
Bottom Layer: Gravel
Fill the bottom of your raised beds with about 6 inches of gravel. This helps fight erosion, helps with drainage, and keeps your crop's roots from coming into contact with the pavement.
Middle Layer: Decomposing Wood
I highly recommend the hugelkultur method. A hugelkultur, or "mound culture" in German, is a raised bed with a base of decomposing wood. Rotting wood encourages fungal networks, holds moisture, and fills the space pretty cheaply. Get some logs, sticks, and other dead wood pieces and make a layer on top of your gravel.
Top Layers: Loose, Rich Growing Medium
There's lots of options for filling this space, but the goal is high-quality organic matter. Avoid bags of potting soil, as these aren't living soil. Living soil self-renews and keeps providing a nutrient rich environment. Potting soil will eventually dry out and lose nutrients. Instead gather things like:
Compost (homemade or purchased)
Coffee grounds (many coffee shops are happy to give out used grounds for free)
Living soil (from your yard or garden, even just a few shovels full will likely contain fungal networks and earthworms)
Grass clippings (not sprayed with anything!!)
Kitchen scraps (egg shells, fruits, veggies)
Leaf mold (leaves that have aged for two years)
Livestock manure
Shredded office paper
Worm casings
Alternate layers of whichever of these materials you're able to get and make a big raised bed lasagna. Save your compost for the top lasagna layer. Then top the whole bed off with mulch! Mulch helps hold water and keeps weeds at bay.
The Best time to Build Raised Beds is in the Fall
You can build beds any time, but building in the fall gives your bed contents time to settle and break down over the winter. Your lasagna layers need time to break down into finished soil, which crops generally prefer. Then just add some more organic matter on top in the spring before planting.
What To Plant
Here's some crop suggestions to go easy on your garden in the first year. After the first year though the sky is the limit!
Beets
Herbs
Leafy greens
Legumes
Onions
Maintaining Raised Beds on Pavement
Irrigate: Even with your fabulous organic material lasagna, your raised bed on pavement will still dry out. Prepare to water regularly, especially in the seed and seedling phase. After your crops get established a deep weekly watering should be enough unless it's extremely hot/dry.
Fertilize: During the summer, add some liquid fertilizer every couple of weeks (during your watering sesh) to push nutrients down into the soil. Some great liquid fertilizer options are comfrey tea, fish fertilizer, and worm tea.
Soil Renewal: Every fall top your beds off with some new organic matter. Over time your raised beds will decompose and sink, so fill those babies back up so they're ready for next spring! And don't forget to mulch!
Aerate: As your layers decompose you'll want to do some gentle aerating with a digging fork to keep the soil loose and crumbly.
Use Cover Crops: Cover crops help enrich the soil and keep it from drying out.
Summer cover crops: Buckwheat, cow peas, millet
Winter cover crops: Daikon radish, oats, winter rye
Happy growing!!
I love these ideas for cover crops - thank you! So glad I came across your Substack 💗