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Wednesday - December 02, 2009

From: San Diego, CA
Region: California
Topic: Compost and Mulch, Soils
Title: Area needing soil amendment in San Diego
Answered by: Barbara Medford


I have a dirt area in the corner where my fence comes together. The dirt is clay-like and during the winter the area gets very little, if any, sun and during the summer it gets 4-6 hours of sun. What could I grow here?


We can go to our Native Plant Database and find several plants that need sun (6 hours or more of sun daily) or part shade (2 to 6 hours daily), but first we need to address the poor soil in your fence corner. While clay has nutrients in it that plants need, it compacts so readily that the tiny little rootlets on plants that are responsible for picking up nutrients and moisture from the soil cannot access them. Since it is now cooler weather and perhaps you are getting some rain, we would suggest you take the opportunity to amend your soil by digging some organic matter, like compost, into it. Really fluff it up and raise the surface level a few inches with the addition of the compost, and not only will the micro-nutrients in the soil be more available, but the drainage will improve a great deal.

Now, on to the plants. You didn't say if you wanted a flower bed, a tree, shrubs, or what, so we are going to go to Recommended Species, click on Southern California, search first on "herb" (herbaceous blooming plant) under General Appearance, then "shrub" and then "tree." You could also search on "grasses" or "cacti and succulents" for more variety. We will give you some suggestions, and you can go from there. Follow the plant links below to find out more about each plant.

Herbaceous blooming plants for Southern California:

Eschscholzia californica (California poppy) - 1 to 2 ft. tall, blooms orange, yellow, February to October, low water use, sun

Penstemon eatonii (firecracker penstemon) 2 ft. tall, blooms red May to August, low water use, part shade

Shrubs for Southern California:

Amelanchier alnifolia (Saskatoon serviceberry) - 3 to 15 ft. tall, deciduous, blooms white April to June, medium water use, sun, part shade or shade

Arctostaphylos patula (greenleaf manzanita) - 3 to 15 ft. tall, evergreen, blooms pink April to June, medium water use, sun

Trees for Southern California:

Cercis canadensis var. texensis (Texas redbud) - 10 to 20 ft. tall, deciduous, blooms pink, purple March and April, medium water use, sun, part shade

Chilopsis linearis (desert willow) - 15 to 30 ft. tall, deciduous, blooms white, pink, purple April to September, low water use, sun

From our Native Plant Image Gallery:

Eschscholzia californica

Penstemon eatonii

Amelanchier alnifolia

Arctostaphylos patula

Cercis canadensis var. texensis

Chilopsis linearis




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