Category Archives: gardening tips

Garden Tasks for Late Fall

honey_mushroomsIt came out of the earth suddenly, pushing soil and plants that were in it’s way to the side. Just a bit of moisture had allowed this large clump of honey mushrooms to emerge and start its path to reproduction. At this time of year when the trees are turning the color of flame and some have already gone into dormancy it seems the earth is growing silent. Winter will soon be here. For nature life continues. Look around you and be thankful for the bounty, the restfulness, the time to enjoy these beautiful mountains that we call home.

The Giant Pacific salamanders in the forest duff are resting up for next seasons batch of young. Maybe now that we’ve had some rain the deer will have something to eat other than my garden. young_buckAs the weather cools, my garden plants are looking past their prime. The seed heads that remain invite small song birds to feast on what remains. Chickadees hop from plant to plant. They even find something to eat in the Japanese maple leaves and the old dried hydrangea flowers that have turned a dusty rose color. Spotted towhees scratch for seeds buried under fall leaves. I’m always slow to cut down and clear everything away but  there are some things I should be doing this autumn. I’ll pay if I leave everything for next spring when it all needs doing at once.

First, I’ll cut back perennials such as hostas, asters and mums, which collapse into a gooey mess and shelter slugs and snails. I’ll pick up and dispose of diseased  leaves, especially under the roses to prevent pathogens from spreading. Coneflowers, ligularia and rudbeckia flowers and ornamental grasses can stay to contribute winter interest for me and the birds.

I’ll leave as much foliage as possible to provide cover, protection from cold winds and foraging spots for other critters and good insects. I’ll wait to cut back the stems and foliages of not only the grasses but evergreen perennials, salvias, hardy fuchsias until spring. There are few things as rewarding as seeing your winter garden turn into a sanctuary for wildlife.

As weeds emerge I’ll spend a little time here and there keeping up with them. There are 300 dormant weed seeds per square inch of soil and I don’t want to add to that.

I don’t have the space to plant a cover crop so I like to top dress the soil with compost or bark chips. I have a few new trees that need staking to secure them through the winter. This prevents breakage and allows new roots to grow deep and stable. Be sure to set the stake on the windy side of the tree and tie loosely so it has some wiggle room This movement stimulates the trunk to grow thicker. Come next summer the trees will  probably be ready to stand on their own. I don’t want to keep them staked longer than necessary. Also check any trees or shrubs that were transplanted and are still tightly bound to a stake. Remove or reset the stake so the trunk will not become girdled as it grows.

OLYMPUS DIGITAL CAMERAA word about all those leaves that cover the ground, the lawn and the perennial beds at this time of year. You can build up your garden soil by running a mower over them to chop into smaller pieces and spread over the soil. Worms and other organisms will start to break them down right away. Next spring dig what’s left into the soil. If you leave more than an inch or two of whole leaves on top the rains will compact them into a soggy mess and prevent oxygen from reaching the soil. If you have too much of a good thing when it comes to leaves, it’s best to put them into your green waste can.

Hummingbirds still need a nectar source at this time of year. Anna’s hummingbirds live in this area all year long.  They need your nectar even more in the winter when very little is in bloom. My abutilons are a winter favorite for them in my garden. Keep your feeders up year-round and keep them clean.

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.

What to do in the Garden in September

I never want summer to end. Who doesn't love those long days and warm nights? The calendar might say fall is near but Indian summer is one of the our best seasons so I love this time of year, too. But then I get all excited when spring rolls around and everything is in bloom. It's all good. I have a check list of some garden tasks  I need to do at this time of year so I better get to them between hiking and trips to the beach.

Fertilize shrubs lightly one last time if you haven't already done so last month. All shrubs, especially broad-leaved evergrimperata_cylindrica_rubrum2eens such as rhododendron, pieris, camellia, hebe, need to calm down, stop growing and harden off to get ready for the winter cold. Some plants have already set next year's buds.

Roses especially appreciate a bit of fertilizer now, encouraging them to bloom another round in October. To keep them blooming make a habit of pinching and pruning off old flowers. Always cut back to an outward facing branchlet with five leaves. There are hormones there that will cause a new rose to grow much sooner than if you cut to one with only three leaves. You can always cut lower on the stem if you need to control height.

Deadhead flowering annuals and perennials in the ground as often as you possibly can. Annuals like zinnias and cosmos will stop blooming if you allow them to go to seed. The same is true of repeat blooming perennials like dahlia, scabiosa, echinacea and lantana. Santa Barbara daisies will bloom late into winter if cut back now.

These plants know they're on this earth to reproduce. If they get a chance to set seed the show's over, they've raised their family. Try to remove fading flowers regularly and you'll be amply rewarded. If you want to start libertiaperennial flowers from seeds this is the time so that they'll  be mature enough to bloom next year.

Now through October, divide summer blooming perennials like agapanthus, coreopsis, daylilies and penstemons that are overgrown and not flowering well.  You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart but sometimes they don't bloom the first spring afterwards due to the energy they use re-establishing themselves.  If you're on  a roll out in the garden, though, go for it now.

It's still a little hot to plant cool season veggies starts in the ground. They appreciate conditions later in September when the soil is still warm but temps have cooled. It is OK to plant seeds of beets, carrots, spinach, arugula, mustard, leeks, onions, peas, radishes and turnips.

If you aren't going to grow vegetables in the garden this fall consider planting a cover crop like crimson clover after you've harvested your summer vegetables.  Next month I'll talk about how to go about doing this and how this benefits your soil.

Cut back berries vines that have produced fruit.  Canes of the current season should be trained in their place.

OLYMPUS DIGITAL CAMERASpider mites are especially prolific during hot, dry weather.  Sometimes you don't even know how bad the infestation is until all your leaves are pale with stippling.  Periodically rinse dust and dirt off leaves with water.  Spray the undersides of infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides. 

Now that you've taken care of your chores reward yourself by  to your garden for color in late summer through fall. Take a look at the garden areas that aren't working for you and replant. Good choices include aster, chrysanthemum, coreopsis, and gaillardia. Abutilon also called Flowering Maple come in so many colors that you probably need another one in your garden.  Petite Pink gaura looks fabulous planted near the burgundy foliage of a loropetalum. Don't overlook the color of other foliage plants like Orange Libertia and Japanese bloodgrass in the garden.

One last to do:  Make a journal entry celebrating the best things about your garden this year.