Ever since sprucing up our evolving outdoor space last summer, we've been trying to find the best ground cover to fill in the cracks between our blue stone patio. Having spent an inordinate amount of money on this seemingly simple space, I thought I would share what I've learned and what I wish I hadn't.
Before getting down to business, I should mention that this is not a post for serious gardeners. It's more a consolation/word of caution to newbies and plantkillers like myself. Despite the morally unacceptable number of plants that have died under my watch, I seem to have a sick and unstoppable optimism that leads me to try again and again...and again.
OK, now back to ground covers. The first step is to read every garden forum on the web that contains advice for your region! I found online local advice to be infinitely more valuable than even the advice given to me by local nurseries, which obviously have an interest in selling heaps of expensive ground covers. Search for conversations in your locale. Ground covers that flourished in your neighbor's yard are likely to flourish in yours too. For example, quite a few people on the mid-atlantic region garden forums cautioned against using elfin thyme, saying that it died within weeks of planting, despite claims of it being one of the hardiest covers. However, everything I read on nursery pages assured me that it would be a great fit. Nope, and with $200+ worth of fried elfin thyme taking up space on my patio, I can tell you that I wished I had heeded the advice of the locals.
The second is to keep it simple. After spotting a beautiful spread in Martha Stewart Living in which an intricate collage of different creeping groundcovers effortlessly intermingled across the page, I decided to repeat the scene in my own backyard. However, I quickly discovered— once again— that my own life is not a staged Martha spread. Different plants take longer to grow than others, and some varieties of creepers like the sedum sieboldii and creeping jenny took off and quickly stifled the growth of its slow growing neighbors. In retrospect, I should have chosen one or two varieties instead of six— seriously, who does that?— and planted them with plenty of room to spread.
Thirdly, be patient. Creeping ground covers do just that. They creep, they don't explode. I grew impatient after a few weeks of looking out the patchy scene pictured above so I began to fill in with more plants. As soon as some began to grow, others would encroach on their ground, and eventually one or both would die.
Now, it's time for all of you savvy and successful ground cover growers to spill the beans. Which varieties have worked for you? How have you spaced them? What's your secret?
(Image: Leah Moss)
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Pay attention to water. If the ground cover is expected to flourish in bright sun, you need to water probably at LEAST once a day until it's well established. I wonder if using those hydro crystals that retain water for plants would help? (It would mean digging soil out around the pavers, mixing in the crystals, replacing the soil with the crystals and plants watering a lot, and keeping your fingers crossed!!!) (Once the roots are happy, less water is required.)
Since my yard is mostly shady, I'd try actual moss. I could harvest it from my own yard or a neighbor's ( most people think of it as a weed they want to replace with grass!) Otherwise, there are online sources from which it can be ordered. Or you could use the buttermilk and blender approach to seed the spaces with moss that has been pulverized. (Another thing to keep moist until established.)
Or stick with the ones that worked -- creeping jenny and sedum sieboldii...
"The first step is to read every garden forum on the web that contains advice for your region...Ground covers that flourished in your neighbor's yard are likely to flourish in yours too."
Just talk to your neighbors. If you like their yard, ask about it. If the're outside working, stop to chat! Just by doing that, my block has started swapping plants all over the place. We divide, transplant, and share plants, advice and conversation. It's a great way to build not only a garden, but also a community!
My mother would do what she calls the 'barefoot test' for a stony surface like this - try walking on that blue stone on a sunny day - ouch! ouch! ouch! You'll burn your feet - and if it hurts your feet, just think what it will do to any plants or moss you try to grow there. So if it's particularly hot (which if it's stone, it will be) do research into heat-loving ground cover. Or you need to break up the hot surface of the stone by using a few tricks:
1. Create a microclimate with an outdoor dining set! Tables, chairs, and a nice umbrella will provide shade and will help your ground cover cool off.
2. Place container plants with tall, sun-loving plants around the stone space - they'll again, provide shade, and the area around the container will be much cooler. I highly suggest using terracotta for this effect - and if you want to encourage moss growth, wet the terracotta and lightly brush with natural, unflavored yogurt, and let it sit for a day or two before planting - lichens and moss will quickly colonize the yogurt.
3. Actually, your decision to get several varieties of plants (six, in this case) isn't so bad for the sake of experimentation and trial and error. It's good to try a few different types of plant to see what does well (in your case, the sedum sieboldii and creeping jenny).
And if it's that hot, plant a succulent ground cover like a sedum... they don't need much water at all and can take a tromping, just ask my dogs.