Arctostaphylos | Leslie Patten Books: Wild Places, Sacred Spaces

California natives Part 3 Groundcovers…Manzanitas and Ceanothus

Posted on November 29, 2009 by Leslie

In this small series of posts on California natives for the garden, remember I’m trying to keep it simple and successful for the home gardener. Most of the time when a homeowner asks for a low or no-water garden and I give them what they want, they always over water regardless. Therefore, in general, unless you know what you’re doing, its better to incorporate natives that will tolerate or even thrive with occasional additional watering.

One of the main tips for growing any kind of native, and most Mediterranean plants in general, is good drainage. California natives are adapted to cool wet winters and dry summers. When planting natives in general, especially Manzanitas and Ceanothus, the main thing you want to watch for is planting the crown of the plant too low. A brilliant idea for helping drainage along is to plant that crown on a little hump, maybe 6″ high. When the crown of these plants stays constantly damp, then rot sets in. Planting on a slight mound insures some run-off. Also, don’t put your drip emitter right on top of the crown, and move that emitter every year farther and farther out to encourage roots to grow outward. Eventually, you may be able to eliminate watering once established.

Both Manzanitas (Arctostaphylos sp.) and Ceanothus are sensitive to over watering, especially true with Ceanothus. Many Manzanitas on the market have been cultivated to be more forgiving and accept landscape watering. Two groundcovers I like are Arctostaphylos uva-ursi ‘Woods Compact’ and Arctostaphylos edmundsii ‘Carmel Sur’. From my personal experience, I have found that the uva-ursi sp., though touted to be more acceptable of hotter weather, are more sensitive than the edmundsii. I find the Carmel Sur variety to be easy and forgiving.

This was an example of a small front yard right after installation. I did very little soil amending on the thick clay soil. Instead I brought in about 10 yards of no animal manures (these harbor fungus as they break down as well as heat) composted soil and planted directly in that. Manzanitas are very susceptible to fungus dieback, and especially the groundcover varieties. I don’t recommend over head watering for that reason in the summer. I also don’t recommend a bark or natural mulch as any splashing water can cause fungus on the stems to grow. So instead here I experimented with a decorative rock mulch.Here is the yard one year later. Unfortunately, several years later, this Arctostaphylos ‘Woods Compact’ did experience some major fungal dieback, probably after an El Nino year, and needed some new plants to fill in.

Seeing that I was having more than usual dieback with uva-ursi plants, I switched to ‘Carmel Sur’ and have had more success, although these plants are about 10″ instead of 6″ high. But the Carmel Sur can take a bit of shade as well as sun, and some summer watering if desired.

I think the larger Manzanitas are easier to grow with less problems than the ground covers. I have had occasional deaths with no warnings, but planted on a hillside, they can take sun or dappled shade with no problem.

Word to the wise: Don’t forget Manzanitas are browsed by deer!

Ceanothus is the quintessential California native. There are many beautiful Ceanothus, or California Lilacs, from tiny to tree-like, able to be grown as ground covers or espaliered against a wall. In general, they are all sensitive to excessive water and crown rot. Whole books have been written on Ceanothus and I couldn’t begin to cover them here.

Below is Ceanothus g. ‘Hearts Desire’, a gloriosus variety. Planted 3′ on center, this low growing Ceanothus is deer proof and very attractive. I’d used in on a small scale with success, but decided to take my chances on a very large hillside installation. After two winters, the Ceanothus is filling in quickly and nicely.

See how large and steep is this hillside, yet poor drainage

See how large and steep this hillside yet poor drainage. Ceanothus filling in nicely

Below is Ceanothus Hearts Desire in a small yard

Here is another hillside example I used with mixed perennials. This slope filled in quickly as well and is large scale.

Ceanothus 'Diamond Heights' is right of the fountain. It has now covered the pebbles

Ceanothus Diamond Hts. right of fountain. Now it has covered pebbles

Below is an unusual newer Ceanothus horizontalis ‘Diamond Heights’. Use it for accent or in pots and not in the hottest of areas. This area is irrigated with good drainage. The Ceanothus is the yellow in front, although now it has filled in completely.

For more information on gardening with California natives, as well as a list of month-by-month native blooming plants, see my eBook Gardening for a Dry California Future. In it I cover what is a true native, planting natives, more types of reliable natives for gardens, and using mediterraneans in combination with natives. Also tips on low water vegetable and fruit tree gardens, how to irrigate for low water use, and making the most of your microclimates.