This weekend I hit the
Yard Garden and Patio show and got the shot in the arm I needed to get me really excited about spring. I only made it to two seminars, sadly, but they both were great. I headed over to the Right Plant, Right Place seminar (Dan Heims, Terra Nova Nurseries). I was feeling sort of "pfft" about it, but the main hall was getting crowded, I was getting tired, and I can sit happily for hours and listen to people talk about plants. It was a treat when they announced that Dan got stuck in Boston in the snowstorm and Maurice Horn of
Joy Creek Nursery would be talking about using gravel in the garden.
He described the process of designing a no-water hell strip for five of his neighbors, which was a huge success. Eventually he was asked to design some large hell strips around Reed College. They would receive no supplemental water and they were comprised of the heavy clay soil that's so prevalent here. He talked about two different things: soil prep and great xeric plants.
Xeric plants thrive on very little water but their crowns tend to rot out in our very wet winters. In order to prevent this, they use gravel as mulch, which wicks moisture away from the crown of the plant. They also amend the soil with two inches of quarter ten crushed basalt and two inches of compost. The type of gravel is important. You want crushed basalt, not round gravel, because it travels down into the clay and breaks it up better. Quarter ten gravel has also been washed, which means you won't get fine particulate floating to the top of your beds and forming a concrete crust.
He's also been experimenting with applying gravel to areas of standing water and top-dressing them with compost. This breaks up the water tension and allows the water to percolate down. They have a great article on their blog about
how to improve your lawn using 3/4" of gravel and a top dressing of grass seed.
The old lawn grows up through the gravel and the new seed germinates on top. You end up with an even lawn (you use the gravel to level uneven spots) that requires less water, less feeding, and stays green longer.
Back in the hellstrip, once you've got your soil prepped with gravel and compost, you can put in plants that require no water in the summer. Some of his suggestions:
Arctostaphylos 'Greensphere,' a "perfect small shrub" whose only drawback is that it grows very slowly to 3' x 3'.
Ceanothus 'Dark Star.' Maurice says he loves all the
Ceanothus but he probably uses this one the most. Dark green leaves and dark blue flowers.
Melicytus alpinus (
Hymenanthera), a textural bony plant to 2.5' x 2.5'. This one is covered in intensely white fruit all winter long.
Grevillea victoriae, a 6x6' shrub that blooms nine-plus months per year and requires almost no water.
Cistus 'Elma', which has large white flowers and dark green foliage covered in an aromatic resin that apparently smells amazing.
Halimium pauanum, which has saturated yellow flowers and an eventual size of 2.5' x 2.5'.
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| Image source: Joy Creek Nursery |
Penstemon davidsonii.
Salvia greggii 'U.C. Pink', a hot hot pink bloomer six months of the year.
Yucca 'Bright Edge', a strap leafed plant that tinges red when the weather turns cold.
Oregon Sunshine (
Eriophyllum lanatum), an underused Oregon native that forms a silver mat smothered in yellow flowers.
Sedum kamtschaticum 'Variegatum', which blooms twice and does well in the shade of shrubs.
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| Image source: Joy Creek |
Veronica armena, whose foliage is like pine needles.
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| Photo source: Joy Creek |
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| Image source: Joy Creek |
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| Image source: Joy Creek |
Crocus sativus, or saffron crocus.
This talk got me so excited to replant my hell strip and try the gravel method on our lawn where
the bobcat compacted everything. My hope is to avoid watering in the front yard more than once a week in the summer, so I'll definitely be planting a lot of these. I'm sure Dan's planned talk would've been great but I'm happy that Maurice subbed in. It was just the information I needed.
