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rafaellangerosuna

Help - drowning or dessicating? SF peninsula

Hi all,

My apologies if this is a topic that gets rehashed frequently, but I am new to the combination of clay soils, blazing sun, wind, deciduousness, and aridity that is summer time in the San Francisco bay area (San Carlos/Peninsula in particular).

I have recently started trying to plant an otherwise barren hillside with plants - blueberries, currants, citrus, avocadoes, pomegranates, mulberries, etc.

I'm coming from Miami, Florida and my gardening skills are attuned to the wet, well-drained, and hot climate.

I can't tell if I'm drowning my plants or letting them dry out (or if they're simply going dormant for the fall). My pomegranate (angel red) seems to be dead; the blueberries are browning, and the mulberry I planted went almost completely yellow and dropped most of its leaves.

The ground appears to be drying out between waterings and I'm only watering 1-2 times a week. But I'm working with what I'm guessing is very poorly drained soil because it is rock hard clay.

Can anyone give me tips for assessing if the plants are under-watered or overwatered? Any other locals have a sense of whether its an early fall or whether newly planted plants might be going into the fall leaf drop? Or how (when?) to establish plants on a clay covered, sunny hillside in California?

Thanks in advance.

Rafael

Comments (5)

  • calistoga_al ca 15 usda 9
    9 years ago

    Why try to grow in such neglected soil? Time spent making the soil drain and not the compacted garden you moved into, will make your gardening experience much improved. Trying to start a garden in mid summer is another handicap. When the rains start would be a good time to work on your soil, dig in about four inches of compost to start. Almost all of your shrubs would grow better if started when dormant, and in the winter rainy season. Al

  • lazy_gardens
    9 years ago

    I can't tell if I'm drowning my plants or letting them dry out

    Moisture meter is the answer - get one and use it. Water according to the meter, not the calendar.

    Get the Sunset Western Garden Book - it's invaluable for any western garden - and identify your exact microclimate from their maps. The "bay area" has a lot of small, but distinct, zones. It will tell you what grows well, and what doesn't in that zone.

    Don't look at the nurseries for plant selection - look around the neighborhood and see what's growing well. Nurseries sell all kinds of plants that have no hope of surviving.

    Your key tools will be compost, compost and more compost, added thickly and with mulch on top. And a drip irrigation system.

    Plant at the best time of year - even though you want to dive in, plan exactly what you will be doing.

    Don't plant more than you can take excellent care of for the first couple of years - extend your landscape slowly.

    Consider xeriscaping: drought tolerant shrubs and succulents, native plants, things that can stand drying out. Basically, if it requires "moist garden loam" to grow, don't plant it.

  • stanofh 10a Hayward,Ca S.F. bay area
    9 years ago

    There was a post last year,almost identical to yours. A local bay arean had dead blueberries and some stunted other plants.
    Too dry. A new garden needs much more water then the same plants with roots dug in deep. And a hillside? whoa..very fast draining,easy for water to go by plants in summer and not down. You need to water more,MULCH all the plants. That's all the magic you need.
    On the bluberries...they are heavy water users.

  • Sugi_C (Las Vegas, NV)
    9 years ago

    Rafael,

    Can't plant in that and expect it to thrive.
    I just spent 4 days on my knees or butt digging out soil and amending it down to about 1.5 feet. They say not to till but that's for people who can actually get a shovel in the soil without machinery...I think.

    Anyhow, pull one that is ailing out and see what the roots look like. If they are dry, you didn't get them any water. If they're soaked, you drowned them. :)

    I amend all of my garden soil with lots of compost and Gromulch or Amend. Also add in whatever I must for whatever I am planting (ie. blueberries will need heavily modified soil to make it acidic and even afterwards, you have to continue making sure ph is okay...i suggest you grow blueberries in a large pot if you can.) Then I mix it all up and break ALL the soil up.

    Once the entire planting area is amended, then I dig a hole for the plant, break up all the roots, prune them, plop them in and water heavily for about 2 weeks. Daily, or near daily...especially for me since I severely prune the roots of my usually potbound garden purchases. With only a fraction of roots they had before I planted, they can only drink from the top layer of soil so I keep it moist.

    It's SOOOOOO much work and I feel physically beaten. And if my guy hadn't helped me dig up some of these roots or break ground in some of these "rocks", I'd have never finished.

    But the psychological stress of everything dropping dead on you is worse. Besides, you only need to do it once (per home with this impossible soil -- welcome to California)....and then just keep adding compost on top. I tend to add about 3-4 inches per year.

    If your heart is set on blueberries, there's a nursery in San Mateo that sells a really nice blueberry soil---very acidic. They make it there on site so you might as well pull out the blueberries you planted and pot it up.

    Grace

  • bahia
    9 years ago

    A simple method to check soil moisture; dig up the soil at one side of the rootball and check the soil condition/moisture. If it is only moist the top few inches, more water obviously. If it is too wet and not draining, you may have to better amend your soil, as others mention, compost added as mulch every year is the easy way to do it, the soil organisms and worms do all the work, but there isn't much mixing activity going on if the soil isn't irrigated in the summer.

    Planting in fairly heavy clay at the perfect soil moisture content, (after we've had several good rains in the fall, and you can easily dig a foot deep without clay sticking to the shovel), is the ideal time to plant everything but tender tropicals. You can replicate the softening effects of rain via irrigation, but it can require hours of repeated slow drip irrigation over multiple days to get moist a foot deep.

    Personally, I haven't found Blueberries to be that water demanding in clay soils where I've planted them out, but they do prefer an acid ph soil, which isn't the norm in most bay area clay soils. Planting them in an oak wine barrel sized pot with a good soil mix and 3x a week drip irrigation with sufficient emitters and duration to thoroughly wet the root ball should give you lots of fruit eventually. I like top dressing with cottonseed meal.

    The one photo of your weeping mulberry tree didn't look like your slope was all that steep; in fact, it seemed rather flat. If you don't want to mess with the roots of your already planted trees/shrubs, you're not likely to discover whether you are over or under watering. For new trees, I like using 1/4" dia. emitter line with emitters at 12" on center, and do several spirals around the trunk with about 4~6" spacing between spirals. For water loving trees like the Mulberry, you might start off with 2xweekly irrigation for 15 ~25 minutes a cycle. You could also set up this same irrigation over bare earth, run it for a week, then check by digging to see how deep it's wetting the soil. There is no substitute for direct observation of root growth and depth of soil wetting. If you have nearly pure clay that has a bad smell and blue-black color, then you may be best with importing topsoil and planting on raised mounds or in raised beds.

    If the condition of other plants in your existing garden looks okay, anaerobic clay soil which doesn't drain probably isn't your problem. Once you determine how long, often you need to run drip irrigation for your particular soil conditions, and if you keep adding fresh mulch each fall, your soil should improve greatly over time. There are also suggested plant lists for clay soils, and/or lists of more drought tolerant, wind tolerant plants; get yourself a Sunset Western Garden Book, or check out the on-line info at www.anniesannuals.com. Gardening, raising fruit baring trees and shrubs can be very satisfying here, once you figure out proper soil treatment and irrigation scheduling.