Building a drought tolerant rock garden

Summer in the Thompson Shuswap is hard on plants. Both native and non-native plants can struggle depending on conditions. Gardening with the principle of right plant, right place, will raise the odds of your plants surviving.

Do you have an area of your yard or garden that you refer to as The Hellscape? This is an area that is subjected to the broiling sun, to drying winds and perhaps also to the inability to water this area adequately or not at all. A spot where only the toughest of plants can survive. It is the perfect spot if you feel like you need to challenge your gardening skills.

This year I decided to take on the challenge by planting the area on the south side of our house known as The Gravel Hellscape. It was a strip of weedy gravel that is about six feet by 36 feet.

This was the first time that I had attempted to plant in what was essentially a flat gravel pit. The first thing I did was weed thoroughly and then water it. As expected, not long after, I had an amazing crop of new weeds. So, I weeded and watered it again. This time, fewer weeds.

Another option for weed removal would be to water and then solarize the newly sprouted weeds with a sheet of clear plastic. A few more rounds of watering and weeding and it was time to plan out what plants were going to go where.  Getting rid of the weeds was the most challenging part of the project.

After writing out a list of the exact plants, by variety, that I wanted, I headed out to find them. The plants on my list were found on local and Okanagan nursery plant lists, Okanagan public garden flower listings, as well as Okanagan and Kamloops city plant listings. Not all the plant varieties that I chose were available but there were so many others to choose from.

After purchasing the plants, I started by placing the pots into the spots where I wanted to plant them. This resulted in shuffling the pots here and there several times. I had to change spots because of the different colours that I had ended up with as well as the changes in the new variety of heights.

This is where the artist in you can really shine. When the plants are all still in pots they are easy to move around to get them just right. When creating a new flower garden you have so many options. You can choose the colour palette you want, the height and the shape of the plants, you have choices in leaf and stem colours and textures. Do you want them to be flowering or nonflowering plants? Do you want them to be fragrant? Do you want them to provide interest in the spring, summer, fall or winter?

After getting the plants where I wanted them it was just a matter of digging the holes with a small pickaxe. I found this was the best tool for digging into the gravel. The holes were dug a bit bigger and deeper than usual. This allows the roots to more easily head down searching for moisture where it will be cooler.

I also added a few handfuls of potting soil to each hole and mixed it in with the meager amount of native sandy soil that was there. The holes and plants were pre-watered before planting. I planted on a cloudy day and chose a weather forecast that was calling for three cloudy days in a row. Planting on a cloudy day helps to minimize transplant shock.

After planting they were all watered again and documented in my garden journal. Next spring will be when we find out which of these plants are most likely to be the long-term survivors.

The following is a list of the plant species that I chose. Of the seventy plants there are nine varieties of achillea. The remaining plant species have two to four different varieties. They were all chosen for their drought tolerance and are in the zone three to five range. There will be a continuous display of flowers throughout the spring, summer and fall. Some will provide winter interest as well.

• Achillea

• Sempervivum

• Stachys – edging plant

• Lavendula

• Geum

• Thymus serpyllum – edging plant

• Penstemon

• Cacti

• Sedum

• Leucanthemum x superbum

• Allium

• Echinacea

• Gaillardia

• Salvia

• Lychnis

• Aurinia saxatilis- edging plant

• Agastache

• Oenothera

Valerie Boyda is a Master Gardener with the Thompson Shuswap Master Gardeners. She lives west of Kamloops with her husband and two cats on the north shore of the Thompson River. She loves gardening, photography and fishing and has a keen interest in regenerative landscaping with native plants and trees