Gardening Gone Wild has invited us to a Gardener's Design Workshop, and this month's topic is Covering the Ground. When I heard the topic, I was ready to blog about low-growing annuals and succulents and, of course, mulch. And it's true, mulch such as bark or gravel helps tremendously in a dry climate because it keeps in the moisture. So, three cheers for mulch, which one should I get?
Well, not so fast. How about some groundUncover as well? There are 1600 species of native bees in California, and 70% of them need bare dirt to live in, and raise the baby bees. The Berkeley Bee Garden, a research garden that was open for the Bringing Back the Natives tour, is a great example for groundcover and groundUncover. Colorful annuals, perennials, and a few shrubs such as Ceanothus are interwoven with a few mulched paths and surrounded by quite a lot of bare dirt.
The photo below shows the beautiful gilia, poppies, and penstemon, most not higher than 2-3 feet, making an excellent groundcover, while groudUncover is close by, both a freshly plowed field and a vegetable garden.
And, when you plant it and add some groundUncover, they will come. The staff at the garden handed us a list of plants that provide nectar and pollen year round and attract and support different types of bees at different times. You can also find the list at their website. The Berkeley researchers emphasize natives and include a lot of annuals. They encourage a mix for the summer and fall, and it really works, everyone saw bees. Lots of them. Below a picture from Country Mouse, with a beautiful green bee.
I also asked whether bare dirt in sun or shade is more suitable, and was told sun is preferred. That's good news because my drought-tolerant chaparral plants can probably muddle through if remove some of the bark mulch as time goes by, while the redwood habitat plants really do need a good layer of mulch to keep the moisture in.
I'm seriously thinking about making some bare dirt paths around my ceanothus, which are attracting several different kinds of bees. And I'm wondering whether removing the bark mulch where the Phacelia is growing this year will bring me a small field of those plants next year. I saw such a field at the research garden, and it was quite stunning.
Let's face it, most annuals grow best if you sow them on bare dirt, not on mulch (poppies and clarkies are an exception). Of course I love my Penstemon heterophyllus (a perennial) as a groundcover.
But wouldn't it be fun to have a patch of Gilia right next to it, with a little groundUncover, and the bees happily enjoying the nectar and pollen?
And what about the other 30% of native bees? They live in holes in trees or other cavities, and might appreciate a bee house. The researcher said those houses can work out very well, or not so well, and they've only started experimenting with them. There's actually a lot of good information in German about bee houses, just google Wildbienen. Even if you can't read the text, the pictures tell the story.
P.S. For other most excellent posts about the bee garden, do look at this post by Rooted in California, and this post by How's Robb?, with a cool picture of many different native bees on pins.