Category Archives: mulching

Drought Tolerant Gardening

arctostaphylos.1280Last fall I wrote about the predictions for winter rains in our area. The Farmer’s Almanac predicted our “winter will be much rainier and cooler than normal”. Weather bloggers online posted an impressive number of charts and figures predicting “a general dry trend”. NOAA said we had an equal chance of precipitation totals going either way.

Even my favorite predictor, the Sandhill crane, who started it’s annual migration to the San Joaquin Valley several weeks earlier this year, seems to have gotten it wrong. The timing of their migration has been a good predictor of both wet and dry winters. This year the early migration predicted an early winter with plenty of rain and snow.

Every snowboarder, gardener and nature lover knows we are in a great drought that started last winter. Information about the California drought is all over the news. We are sure to get a few storms in the coming months but there will be no “Miracle March” from what I see and hear from the experts at NOAA and NASA. This extreme weather event will bring voluntary or possibly mandatory water rationing. What can we do to make the most of the water allotted to the garden and not let expensive mature landscaping die unnecessarily? How can you make your garden more drought tolerant?

1) Group plants in your garden according to their water needs. Some can survive on rainfall bush_poppy.1600alone after their second or third season while the perennial beds, vegetable garden and fruit trees will require a different schedule. Late winter or early spring is a good time to transplant those plants that use more or less water than their neighbors.

2) Examine your irrigation system and watering plan for efficiency and minimal waste. Watering in the early morning is the most efficient way to maximize absorption whether you water by drip system, sprinkler, soaker hose or by hand. The water soaks deep in the soil without risk of evaporation. It bolsters the plant for the day and has dried from leaves by evening reducing the risk for foliar diseases like mildew. Plant roots are also more receptive to watering in the morning. Water slowly, deeply and infrequently so there is no runoff. This also allows plants to grow deep roots that can go longer between waterings.

lupine_silver.16003) Using vegetation or mulches to cover bare soil is a key ingredient to slow down runoff. Maximize what soaks into the ground.  Mulches are a good choice for areas with less than 33% slope, Vegetation works well on areas with less than a 50% slope. Mulch can be organic-such bark chips, straw or grass clippings or inorganic gravel or cobbles. All protect soil from erosion and conserve soil moisture. Organic mulches keep plant roots cool, encourage earthworms and other beneficial organisms and prevent weed growth. Your plan should be to slow, spread and sink water back into the ground whether it be from rainfall or irrigation.

Of all the types of mulches, recent studies have shown that ramial bark chips are one of the best mulches to improve soil health. Ramial chips are those from trees and brush, from branches up to about 4″ in diameter with or without leaves. Deciduous hardwood is best but all chips are good These chips contain a high percentage of thin young bark and young wood. This is what makes them so valuable to the garden. Young wood is the trees factory for producing protein, glucose, fructose, lignin and polysaccharides. It’s an important source of nutrients for living things at all levels according to a study by 2 soil scientists, G.  Lemieux and R.A. Lapointe.  You can obtain these kind of chips free from tree trimming companies like Davey Tree who is probably working nearby chipping roadside brush for PG&E.

Water makes up 90-98% of every plant we grow. It’s needed for photosynthesis, as well as reproduction and defense against pests. Improving your soil’s ability to absorb and hold water should be a priority when you’re out in the garden. Help ensure the health or your trees and garden by following these steps.

Growing Cover Crops – Part II

Orin_Martin_bell_beansOrin Martin of the Alan Chadwick Garden on the UCSC campus is widely admired for his incredible knowledge and skills as a master orchardist, horticulturalist and teacher. I was lucky a couple of years ago when he visited a group of fellow designers and brought his favorite russet apples. Another time he brought a dozen different kinds of potatoes that we roasted, critiqued and thoroughly enjoyed.

The Alan Chadwick Garden was nothing but poison oak and chaparral in 1967 when Alan Chadwick first got his hands on it. Martin came to UCSC in 1969 as a literature major but was soon impressed with Chadwick’s work, preaching the gospel of treating the garden as a self-nourishing system. Together they worked the garden, building the soil and teaching others.

Now Martin runs the appreaster_Michaelmas_daisy.2048ntice program which teaches future organic gardeners and shares his knowledge in workshops like the Cover Crop class I recently attended.

Last week I wrote about how and why to plant cover crops. This is what to do next spring after they’ve done their magic in the soil fixing nitrogen.

Cover crops are plowed or skimmed off in late February to early April. Because it takes 3-5 weeks for the cover crop to break down so crops can be seeded or transplanted, it is often best to skim off the cover crop at the base of the plants and combine with straw or leaves to make compost. Previously made compost can then be applied to the surface. It is important to retain the roots and nitrogen-filled nodules in the soil. Take only the vegetative portion.

cover_crops_Orin_Martin.1280Another method is to skim the foliage with a weed wacker or mower chopping it into small pieces 1/4″ to  4″ long. You can then rototill this into the soil and allow it to decompose on its own. In about 2 weeks the material should be broken down to be unrecognizable as plant material before replanting.

If you are developing your soil to build organic matter and improve structure incorporate the cover crop at a more mature stage (half to full bloom) when it has a higher carbon content. The nutrients will be stored in the reservoir of humus and released slowly over a number of years.

On established soils where you want primarily to fertilize next spring and summers crops, incorporate the cover crop after skimming and chopping when it has just started to flower as it decomposes quickly at this stage.

The Chadwick Garden fertilizes its established fruit trees by simply cutting down the cover crop growing at their base with a machete at the 25% flowering stage. 4-6″ of wood chips are laid over the chopped up pieces and left for nature to decompose. That’s all their is to it. Martin explained that the garden used blood meal and the organic fertilizer, Sustane, during the first several years while the trees were becoming established.

Picking up a clump of grass sown just 2 weeks ago, Martin teased off the soil to show the vigorous, fibrous root mass. “This is why the riches soils of the world, the Steppes of Russia and the original Midwest prairies, are so fertile and are called bread basket soils”, he explained.

Plant a cover crop this fall and your soil will be richer for it.

Growing Cover Crops- Part I

Every drop of rain that hits bare soil is destructive. Over 3000 years ago the Chinese knew how to protect their soil from erosion and increase fertility by planting cover crops. Early Nile Valley inhabitants 3500 years ago also practiced this method of agriculture as did first century Romans. Lupines were planted in poor soil when no animal manure was to be had. I learned this and also how to protect and improve my soil from Orin Martin, manager of the Alan Chadwick Garden at a cover crop workshop recently on the campus.

aster_Michaelmas_daisy.2048“It’s all about the biology of the soil”, Martin said. “You grow the soil that helps you grow the plants”. A cover crop is really anything that covers the soil and protects it from rain, trapping nutrients and preventing them from leaching downward, he explained. Cover crops can increase the tilth of the soil. Quick germinating grasses easily loosen the top foot of soil with their root mass. Legumes have a tap root, a bio drill, that penetrates 30″ downward while alfalfa roots can grow even deeper.

Cover crops like bell beans, vetch and fava beans are especially valuable as they increase nitrogen levels in the soil in two ways. Atmospheric nitrogen can be “fixed” and left in the soil to fertilize subsequent crops. This is in addition to the nitrogen left from the foliage of the legume.

Cover crops are also called green manure when they are chopped up and turned into the soil in spring lettuces_after_cover_cropping.1024before going to seed. The planting of legumes like peas and beans can actually increase nutrients in your soil giving you a net gain which is needed to offset what you take out of the soil when you harvest fruits, vegetables and flowers.

From late September to the end of November is the best time to sow cover crops. You will need to irrigate lightly a couple times per week if it doesn’t rain. You can also wait to sow just before the rains start. Be careful about working overly wet soil however as you can ruin the structure of your soil.

The Chadwick Garden, Martin explained, originally was heavy red clay. 35 years of soil building with bell beans and vetch cover crops and compost have established a level of fertility that now supports several acres of vegetables, fruit trees, berries and beneficial flowering plants. Fall-sown, spring ploughed-down cover crops are the sole fertilizer used for the better part of the last decade.

Soil_builder_cover_crop_mix.1600Martin explained that recent research now recommends planting a tandem of grasses and legumes. Annual cereal grasses such as oats, rye and barley germinated quickly to hold and shield the soil until the legumes take hold. Bell beans, fava beans and vetch which are the best legumes for our area grow slowly the first 3 months then take off growing 70-80% in the last 3 months. The ratio of grass seed to legumes can vary from 10% to 30%.

There are other legumes that fix nitrogen but no where near as efficiently as bell beans.  Crimson clover seed is also more expensive, needs lots of water to sprout and competes poorly with weeds. Mustard causes competition with the fruit trees as bees will concentrate on the mustard flowers instead of the fruit tree flowers.

A question came up about using inoculants on legume seed. Martin explained that our soils have a native resident population of good bacteria that will break down the seed coat and encourage the plant roots to fix more nitrogen especially after cover cropping for a few years.

We all followed Martin out to the cover crop trial plots to see how the different types were growing. Bark chips will soon be applied to the paths. All of the gardens are mulched several times per year with wood chips. A 10 year study, Martin explained, demonstrated the amazing benefits of ramial chipped wood which is the type the tree service companies provide for free.

We watched him work the soil lightly with a metal bow rake then broadcast 8-10 seeds per square foot. Weeds were already cleared but Martin said this step doesn’t have to be perfect. Afterward the area was raked again lightly 1-2″ down and covered with 3-4″ of straw. Wood chips would be fine, too. Mulch heavier if you have bird competition. Cover crops are vigorous and will come up through just about anything, he said.  Water in lightly.

There are 3 ways to fertilize, Martin said. You can buy chemical fertilizer which is expensive and doesn’t do much for the soil. You can apply compost, which being carbon based, ramps up beneficial fungal organisms in the soil. Or you can cover crop or grow green manure which increases beneficial soil bacteria. Orin Martin has proof of the benefits of the last two methods.

Good Watering Practices

philadelphus_Covered_BridgeThe recent heat wave was one for the record books. The temps were not the highest we've ever had around here but as each day melted into the next I kept thinking that fog, nature's air conditioning, was surely on it's way. Even drought tolerant plants need a little help at these times.

Watering is crucial as plants are growing vigorously. Water makes up 90-98% of every plant we grow. It's needed for photosynthesis, as well as reproduction and defense against pests. Checking soil moisture and improving a soils ability to absorb and hold water should be a priority when you're out in the garden. Don't wait for plants to wilt and burn before correcting watering problems.  

There are ways to water more efficiently and ways to conserve that water. Now is the a good time to review some good watering practices and guidelines.

When is the best time to water? Watering in the morning is the most efficient whether you water by sprinkler, drip system, soaker hose or by hand. The water soaks deep in the soil without risk of evaporation. It bolsters the plant for the day and has dried from leaves by evening reducing the risk for foliar diseases like mildew. Plant roots are also more receptive to watering in the morning.

Is it true that water droplets will scorch leaves in the sun? According to a study published in New Phytologist, a journal of research in plant science, there is a slight risk of leaf burn on fuzzy leaved plants in the sun. The hairs can hold the water droplets above the leaf surface and act as a magnifying glass to the light beaming through them. The study also reported that water droplets on smooth leaves, such as maples, cannot cause leaf burn, regardless of the time of day.

I my forty years of gardening, my own observation is that the leaf burn on a fuzzy leaf must be very small, indeed, as I've never observed any damage. If you find a plant needs water midday, by all means go ahead and water it. Containers even benefit from the cooling effect that watering provides

Most plants need 18" depth of well-drained soil to thrive although trees and many vegetables roots grow several feet deep. More than an inch of water per week may be needed for their success and in the case of many trees and native plants, deeper but more infrequent watering is required.

You can easily measure how much water you are applying. If you have a sprinkler system, place a straight-sided container like a tuna can on the outside edge of the area being watered. Let the sprinkler run until one inch of water has accumulated in the can. When using a drip system or soaker hose, irrigate until a 3" deep test hole dug 1 ft out from the emitter or end of the soaker is moist. Moisture at that level indicates than an inch of water has been applied. The best way to determine how many inches of water your soil needs for a good soak is by digging down after the water has had a chance to settle. When watered well, the soil should feel cool and damp at the bottom of the hole. If the soil feels warm and dry you haven't watered long enough. You need to do this test just once to get a feeling for how much water your soil can hold and how deeply it's soaking in.

if you have a lawn, decide if you really need it that large and maybe not in the front yard at all.  Keep the mowing height high during the heat of summer.  Mow when the grass is about a third taller than recommended height. For common fescue, mow when the grass is 3-4" tall, with your mower set at 2-3 ".  Fertilize only when your lawn needs it to keep a good green color.  Over fertilizing results in quick top growth which needs more water and is susceptible to insect damage and fungus problems.  A good rule of thumb for watering a lawn is to water 1 x per week when the temperature is 70 – 80 degrees., 2 x per week when it's 80 – 90 and 3 x per week only when it's above 90 degrees.  Make sure the water soaks in encouraging the roots to extend  30" below the surface which will make your lawn more drought tolerant.
 
Consider replacing your lawn with a walk-on ground cover like woolly thyme or chamomile.  You can't play touch football on these ground covers but they will tolerate light foot traffic.  Another alternative is to plant low growing native grasses that require only a handfull of trims per year compared to a conventional lawn.
 
Water wisely in other areas of your garden.,  Construct soil basins and furrows to direct water to plant roots and increase this basin as the plant grows or use a soaker hose on the surface to slowly water at the drip line of trees and shrubs. Fruit trees, citrus and flowering trees need a deep irrigation every other week. Less thirsty established trees like Chinese pistache and strawberry tree need irrigation about once a month. Newly planted trees need water regularly. Gradually reduce frequency after a year or so.

And above all, mulch, mulch, mulch.  Cover the soil with at least 2" of organic mulch such as compost or chipped bark.  The mulch holds in moisture as well as keeping roots cool and gradually decomposes and enriches your soil.  Keep it away from the base of trunks or plant stems. Don't use rocks or gravel as a mulch because they add heat to the soil and moisture evaporates faster.

Take good care of your plants this summer.
 

Early Summer Tips

hydrangeas2 3Some things in the garden need to be planned out in advance while others happen by chance. For instance, this year when our spring rains stopped dead in their tracks I gave up adding any more acidifier to my hydrangeas. You need to change the pH of the soil around hydrangeas well before they set buds. I like mother nature to water for me early in the season and she didn't cooperate.  As luck would have it, the flowers this year are majestic purple, mauve and magenta where before they were sky blue. Frankly, I'm thrilled with this years color palette. Hooray for serendipity.

Early summer is the right time, however, for many other garden activities that you don't want to leave to chance.

Many plants, both vegetable and ornamental, are bothered by aphids and other sucking insects as well as foliage and flower eating bugs
.   From cucumber beetles, flea beetles, stink bugs, weevils, curculios to borers , the list of trouble makers is endless. .  To help deter them mix up some pepper spray in your kitchen.  
    1 tablespoon hot pepper sauce or 1 teaspoon cayenne pepper
    6 cloves garlic, crushed
    1 quart warm tap water
Let stand I hour, strain and spray plants either in the morning or evening.

Apply the second fertilizer application for the year to your citrus and fruit trees. The last one should be immediately after harvest.  Apply the fertilizer to the soil around the drip line of the tree where feeder roots are located and scratch into the surface. Water in well. As with all fertilizers, make sure the trees are moist before you fertilize. Young trees in their first, second or third growing season should receive half the rate of established trees.

If your fruit trees are starting to produce too heavily, remove excess immature fruits.  Doing so allows remaining fruit more room to grow and prevents branches from breaking under the weight.  When apples, pears and stone fruits such as apricots, nectarines, peaches and plums reach 1/2' in diameter, pick some off, leaving the remaining fruits spaces 6-10" apart along the branch.  Later, to protect your ripening fruit, enclose the tree with bird netting,  hang strips of mylar flash tape near brach tips or substitute old CD's.

If you battle dandelions and don't want to use chemical weed killers around pets and children, get out the white vinegar from the cupboard. On a hot sunny day spray straight white vinegar directly on the weed. This method will kill whatever it touches so direct the spray carefully. If the dandelion is in the lawn, wait a week, pour some water on the dead spot to dilute any lasting effects of the vinegar. Then poke a bunch a holes and drop in some grass seed. Sprinkle a bit of fertilizer where the seed is planted and keep the area moist. In three weeks you won't remember where the dead spot was and the dandelion will be long gone.

Another garden to-do this month includes summer pruning of wisteria. To increase flowering next spring and keep these vines under control cut new growth back to within 6" of the main branch. If you want to extend the height or length of the vine, select some of the new streamer-like stems and tie them to a support in the direction you wish to train the plant.

To encourage continued bloom on annuals, perennials and shrubs, remove faded flowers before they start to form seeds.  Make sure you remove the entire flower head and the base where seeds form ( such as the bulbous part of dahlia, petunia or fuchsia flowers) and not just the petals.  Cut the stem down to where leaves start.  The season has just started and you'll be enjoying lots more flowers in the months to come if you deadhead regularly.  
    
Another maintenance tip is to shear spring blooming perennials to keep them full and compact.  Candytuft, phlox subulata, aubrieta and other low growing perennials benefit if you cut off spent bloom and an inch or two of growth.  Other perennials and shrubs that benefit from the same treatment to keep them compact are erysimum, lavender and Pink breath of heaven.

Also re-apply mulch if it's getting thin in spots. Check ties on trees to make sure they aren't cutting into the bark. Cultivate lightly around trees to discourage weeds and allow water to penetrate.

Don't be afraid to move a plant that is not working where its growing now. Make a note in your journal reminding yourself to transplant it sometime in the fall. Gardening is a dynamic and fluid process. Enjoy piecing  together pieces of the puzzle.
 

Camp Joy, Boulder Creek

Camp_Joy_sign2If you've ever eaten a Camp Joy cherry tomato you'll know why I was excited to be given a tour of the new seedlings in the greenhouse by Jim Nelson, the creator of this beautiful, organic family farm. Since 1971 this non-profit farm has been providing educational, creative programs for kids and adults. It is an example of and encourages others who wish to begin their own sustainable farm.

It was a warm, spring day when I visited and Jim was gently watering the herb, vegetable and flower seedlings by hand using water from a large can that had warmed to room temperature and given off any chlorine that was present. Camp Joy has a spring plant sale coming up April 27th and 28th and another on Mother's Day weekend and Jim was pleased with the progress of the seedlings. They grow proven varieties that do well in our area. Group paintings done by charter school children decorated the wall of the greenhouse.

Outside we were accompanied by Jim's two dogs, Ruby and Rownya, as we admired the garlic crop that will rotated90.kids_painting_in_greenhousebe braided after harvest and offered for sale in the fall along with dried flower wreaths and onion braids.

The farm offers a Camp Joy Cooperative weekly for 3-5 yr olds encouraging them to explore their surroundings through all their senses. Garden tours for school age children or a group of any age are also offered. Everyone at the farm is happy to share what they've learned about growing and preparing food, saving seed, bees and other insects, goats and garden crafts. And there is always something to be picked, harvested, weeded or just enjoyed while having lunch in the gazebo.

Walking along a path bordered by phlox, aster, oregano, iris and nigella we admired a blooming Buff Beauty rose covering an arbor. Jim planted this as well as his favorite Madame Alfred Carrier 42 years ago when he first came to the property. His friend at UCSC, Alan Chadwick introduced him to it. The soft fragrance blended with the blooming lilacs and wisteria.

To maintain fertile soil, a cover crop of fava beans was just starting to bloom in a several areas. Ladybugs were plentiful on the flowers. The beans will be cut down, Jim explained, in about a month. Members of the farm will eat some of the beans while young and sweet and let some mature so they can save the seed. The goats also enjoy fava beans at the flowering stage. There is a fund-raising art program, called Kids for Kids, offered in May, the proceeds going to help improve the goat barn and yard.

lilac_wisteria-arborNext we visited the Kid's Garden. Art, cooking and gardening projects are ongoing in this area. Wholesome, healthy food and beautiful flowers are all part of the farm. The plot of godetia was setting bud and will be offered as cut flowers during the upcoming sales.

Everything is grown with care at Camp Joy. Jim explained that compost is regularly added back to the soil and used to start seedlings in a special blend of "real soil" allowing them to transplant and continue to do well in the garden. He sometimes used kelp and fish emulsion as fertilizer but mostly it's the compost that makes the seedlings so strong.

Camp Joy offers lots of classes for kids and adults alike. Family members and interns are passionate about the farm and enjoy sharing. On this beautiful day, we were greeted with a smile by the person spreading compost.  It was clear that there is a respect for the cycles of the earth and the changing seasons at the farm.

Take advantage of the Spring Plant Sale at Camp Joy. Bring the family and walk through the garden. Visit their website for more information about their events and classes.  http://www.campjoygardens.org