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Saturday - June 19, 2010

From: Penngrove, CA
Region: California
Topic: Drought Tolerant, Shrubs, Trees
Title: Trees and shrubs for adobe soil in Penngrove CA
Answered by: Barbara Medford


Hi, I'd like to find a list of trees that are native, drought tolerant and suitable to the adobe soil in Penngrove. We will be landscaping a bare .5 acre parcel starting later this fall. Another feature that would be nice is "fast growing". Taller shrubs are on our list as well. Thanks, KM


We are going to assume that when you refer to "adobe" soil, you are referring to heavy clay, not materials for building pueblos. This article from Dave's Garden offers a Definition of Adobe Soil.  The pages on individual plants in our Native Plant Database ordinarily list the soils, light requirements and moisture needs of the plant.  Many plants can live in clays, but to make sure that is what you have in your area, we will check not only that the plants we recommend will grow in Northern California, but also in the Sonoma Co. area, USDA Hardiness Zone 11.

Before we go any further, we want to remind you that you don't have to "live" with clay soil. We don't mean you can dig it up and haul it away, but that it can be amended and improved before you put a lot of time, money and plants into growing in it. The biggest problem with clay soils is that they have poor drainage; water gets trapped on roots and the roots drown. That turns out to be one of the most frequent reasons for plants not doing well in a place where they should have done well-poor drainage. 

Since you will be planting in the Fall (the best time), we suggest you read our How-To article on A Guide to Native Gardening.  A little planning in advance can make a world of difference in how a garden does. Let us also recommend that you read Planting Techniques for Trees and Shrubs from North Carolina Cooperative Extension Service. And, on the subject of "fast-growing" trees, we will do our best, but you  need to realize that many fast-growing trees are short-lived and begin to break down and be subject to disease too early. There is no Instant Garden.

Follow each link to the page on that plant and for more information, scroll down to the section "Search Google for...."

Trees for Clay Soil in Sonoma County, CA:

Cercis orbiculata (California redbud)

Cercocarpus montanus var. glaber (birchleaf mountain mahogany)

Pinus contorta (lodgepole pine)

Shrubs for Clay Soil in Sonoma County, CA:

Amelanchier alnifolia (Saskatoon serviceberry)

Calycanthus occidentalis (western sweetshrub)

Ceanothus thyrsiflorus (blueblossom)

Fremontodendron californicum (California flannelbush)

Holodiscus discolor (oceanspray)

Rhamnus crocea (redberry buckthorn)

Sambucus nigra ssp. canadensis (common elderberry)

Symphoricarpos albus (common snowberry)

From our Native Plant Image Gallery:

Cercis orbiculata

Cercocarpus montanus var. glaber

Pinus contorta

Umbellularia californica

Amelanchier alnifolia

Calycanthus occidentalis

Ceanothus thyrsiflorus

Fremontodendron californicum

Holodiscus discolor

Rhamnus crocea

Sambucus nigra ssp. canadensis

Symphoricarpos albus







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