Category Archives: plant care

May – Words of Wisdom

With each new season, we start fresh with high expectations for a bountiful harvest of vegetables and mouth-watering fruit,  fragrant flowers to pick for bouquets and healthy plants to attract beneficial insects to the garden. As the months pass it seems one problem after another crops up. Don't get discouraged, though. Most any condition or disease can be corrected with the right information. I get many emails from readers with some of the same problems that you might have. Here are a few recent inquiries.

 

GARDEN HOSES

One reader asked about the safety of her new hose. The label on the hose states not to drink from it and she is wondering if it's safe to use it to water her organic vegetable garden.

Most of us grew up drinking water from the hose and on a hot day we still do. But is it safe? A recent study by the Ecology Center, a nonprofit environmental organization based in Ann Arbor, Mich., that reviews consumer products addressed potentially hazardous chemicals in gardening tools. The group tested nearly 200 gardening products, including hoses and discovered some disturbing findings.

To illustrate how chemicals can migrate from harden hoses into water, the research team left a section of garden hose filled with water out in the sun for several days. When the water was tested it was found to exceed federal standards for safe drinking water for several chemicals- including 4 times the standard considered safe for phthalates, 18 times that for lead, and 20 times that for BPA, an organic compound banned from baby bottles.

Most garden hoses that are sold are still made of PVC which can leach unsafe levels of lead into water. There are safer options available, though. Food grade Ether-based polyurethane or natural rubber hoses are a better choice. Look for hoses with nickel or chrome-plated fittings as brass can also leach lead into water.

Plants don't generally absorb lead, unless there is a high concentration of it in the soil but who wants to take a chance? With any hose, even one labeled "drink-safe' let the water run until it's cold before you drink from it because bacteria can grow in warm standing water.

CITRUS ADVICE

Another reader asked what she should do for her Meyer lemon which has yellow leaves. I told her that the yellowing is due to insufficient nutrients. First, apply a fertilizer containing nitrogen. There is also a chance that iron, sulfur and magnesium could be in short supply. Look for these ingredients on fertilizer bags and apply as directed. Also don't overwater citrus. Let the plant dry 2" below the soil surface between deep waterings.

LAWN CARE

Lawns also need a deep watering to train roots to grow deep. When to water? One easy method is to walk on the lawn and check in an hour after stepping on it. If it hasn't rebounded the lawn needs water. Also leave grass clippings to decompose after mowing. You'll need to mow about once per week so the clippings are short and can decompose quickly.

RHODODENDRONS

When everyone's rhododendrons but yours are blooming what can you do?  This plant sets flower and leaf buds in late August or September so fertilizing regularly for the next few month is important. Also water deeply when the soil is dry 1-2" deep and mulch the soil around your plant to keep the roots cool and moist. Rhododendrons and azaleas are shallow rooted so don't work up the soil underneath.

Feel free to email your questions to me. I'm happy to help.
 

Trials & Tribulations of a Test Garden

While at the Watsonville Terra Sole Nursery recently, owner's John and Sherry Hall shared with me their experiences growing and experimenting with plants in their own landscape and nursery. From these personal trials, they decide what to propagate and sell in the small, independent nursery they operate on their property.

With a philosophy to share what they learn with their customers, they grow native and unusual plants and other drought tolerant plants that are adapted to our dry summer climate. Sherry told me that they grow their plants as sustainably as possible, hand pulling weeds and collecting snails by hand. They said they propagate and grow their plants without growth regulators or dangerous chemicals. I saw many birdbaths both in their own landscape and in the nursery. Sherry told me they encourage feathered friends like the Western Bluebird to live in the garden to eat bugs. It's a win-win situation.

Sustainable doesn't just get lip service at this nursery. They don't use labels on their containers making it easy to recycle them. And John makes his own succulent garden boxes from 100 year old barn wood. They looked awesome planted up with a collection of various succulents propagated in the greenhouse.

I commented on the hardy geraniums and other plants coming up through the gravel on the nursery floor. John and Sherry both laughed as they told me "it's the best place to propagate some of the plants. Our son works at a big grower nearby and can't propagate some of these plants even in his $10,000 greenhouse".

What were some of my favorite plants that I saw on the tour and which do they think are the best performers?  
In the test garden, a Lemon Fizz santolina, with foliage so brilliant it looked like a lit light bulb, nestled at the base of a burgundy phormium. A blooming euphorbia completed the vignette. Santolinas are drought and deer tolerant. One important thing Sherry has learned from the test garden is how close to plant things. "They get a lot bigger than you'd imagine from seeing them in that cute little gallon can".

They have an extensive coral bell or heuchera collection that they have been testing for the past 4 years. Starting with 80 plants of different kinds, 90% have survived. The fancy hybrids do need some summer water and compost to look their best. The variety Pinot Gris, with molasses colored foliage, really stood out among the rest.

The echinacea were just emerging from dormancy and will bloom during the summer.  They are very dependable in the garden unless the gophers get them, I was told. Agastache is another one of their favorites and the hummingbirds love them, too. They grow many colorful cordyline from clumpers to tall types. They are doing great, Sherry said. "Maybe a little too great" as they get big fast. Gaillardia have been disappointing but maybe they received too much water at the wrong time, she confessed.

In the nursery, I was drawn to the hardy geranium, 'Bill Wallace'. Loaded with purplish-blue flowers, this mounding perennial blooms for a long time. In another spot, I couldn't miss the rich, dark burgundy flowers of the camellia "Night Rider". "It's the only camellia we grow", the Hall's explained. A very slow grower, it's perfect for containers.

At the Spring Trials they bought a flat of a new acacia called 'Cousin Itt'. This plant is very different from the invasive tree we see blooming each winter. A well behaved 30" mound of soft, emerald green foliage it's drought tolerant and would look great near a dry stream bed.

With so many plants to talk about, we ran out of time and ended with the "under-used, under-appreciated" Beschorneria.  This genus of succulent plants belong to the subfamily agavoides and is native to Mexico. The Hall's are concentrating on propagating a variegated variety in their nursery. A tall blooming red spike had emerged from one of the green species.

This is just a taste of the many plants I learned about that day at Terra Sole Nurseries. From drought tolerance, disease resistance, cold and wildlife compatible the experiments continue.

You can find out more about this small nursery at www.terrasolenurseries.com.

January To-Do’s for the Santa Cruz Mtns

A new year in the garden. I'm already starting to make journal entries for January. Not much to shout about in the weather department. We've had dry Decembers before but if January turns out to be the start of 6 weeks of Caribbean-like weather like last year we'll never catch up.

The weather affects how things grow as much as the soil that plants grow in. Remember the cool spring and summer we had while you waited for your tomatoes to ripen? I was just looking at the weather forecasts for 2010 that the Farmer's Almanac predicted. Last May when I first wrote about them they were way off for the first half of the year and at best were hit and miss for the latter half. October did bring rain for us as predicted but they hedged their bets for November calling for "bands of showers" off and on during the month. December for us brought lots of frost and a heavy wind storm.  Although the frost was predicted by the Almanac, I didn't see any "light to moderate rainfall" in December. I put my trust in the satellite map, internet weather sites and my own common sense to judge when to start planting, pruning and transplanting for the season.

This year I'm going to start off right by noting on my calendar at the beginning of each month just what I need to do to ensure a happy, healthy garden.

Here are the tasks to do in the garden in January:

  • Plan for spring. Bareroot fruit, nut, berry and ornamental season runs through the end of February. Don't miss this inexpensive way to add to your edible garden or your landscape.
  • Cut back hydrangeas if you haven't already done so. Apply soil sulfur, aluminum sulfate or other acidifier if you want to encourage blue flowers. You must do this before they set flower buds or it won't help.
  • Prune fruit, nut and shade trees and spray with horticultural oil, lime sulfur, liquid sulfur or copper dormant spray. You should get one more spraying in about Valentine's Day. This is actually the most important one as it's just before bud break. Don't use lime-sulfer on apricots, though.
  • Cut back summer flowering deciduous shrubs and vines.  Don't prune spring flowering varieties like lilac, flowering cherry, plum and crabapple, rhododendrons, azaleas, camellias, weigela and spirea until after flowering but you can cut some during flowering to bring in for bouquets.
  • Control overgrown honeysuckle, potato vine, morning glory, trumpet creeper and pink jasmine by thinning now or even cutting back low to the ground if  they are a big tangled mess.
  • Prune roses towards the end of the month. I'll tell you how to do this later but it's not as hard as it sounds.
  • Bait for slugs and snails

And here are the tasks you should not do in January:

  • Don't cut back grasses yet if you get frost in the area where they grow.
  • Wait to prune back perennials that may have their new foliage damaged in a late frost
  • Wait until February to prune frost  damaged shrubs  if you can tell how far down the die back goes otherwise wait until growth starts in the spring.
  • Wait to prune fuchsias and other perennials until February.
  • Don't fertilize houseplants until March. Because they are resting at this time of year, they use little water.  Don't overwater.  Be sure they are dry before watering.

As always, if you have any questions, feel free to email me. I'd love to hear from you.

Soil Testing & Monterey Bay Master Gardener’s

Master Gardeners rock. I was inspired by the fabulous gardens that I saw on their 2010 Masters Garden Tour and even wrote a column about some of them. Attending the Smart Gardening Fair when it was sponsored by the Monterey Bay Master Gardeners at Skypark in Scotts Valley was always an educational experience. I also read the informative newsletters available on their website. So it was with the same enthusiasm that I attended  the quarterly Monterey Bay Master Gardener meeting earlier this month.

Held at the University of California Cooperative Extension office in Watsonville and open to the public, the meeting lived up the the Master Gardener slogan to "Cultivate Knowledge... by extending research-based horticultural information". The speaker was Cliff Low, owner of Perry Laboratory in Watsonville. If you have ever wondered why your hedge is languishing despite your exquisite care you may need his services.

The lab provides horticultural advising and testing of soil, irrigation water and plant tissue. Cliff works with grape growers in the wine industry, strawberry and cut flower growers and organic farmers as well as home owners and landscape professionals. He can provide fertilizer recommendation for conventional or organic amendments based on soil tests for basic fertility, micronutrients, salinity and alkalinity.

Cliff combines his formal education with real-life solutions and shared some interesting tidbits of his horticultural  knowledge. Grapes, for instance, are prone to zinc and boron deficiencies and may need foliar feeding of these micronutrients. Excess sodium usually only occurs in clay soils. Mediterranean plants thrive in low phosphorus and slightly acidic soils.

I also learned that rose growers for the cut flower industry in this area now use coconut coir as a growing medium. Coir, which is the hair of the coconut shell, is also being used by gardeners as a substitute for peat moss. Although peat moss has natural anti-microbial properties, it is harvested from rapidly depleting peat lands and is not sustainable. Coir has similar properties to peat as a soil amendment and the high potassium chloride in coconuts may guard against garden pests as it does in coconut trees. The down side is the cost of shipping as most coir comes from Sri Lanka, Mexico and the Philippines. Also weed seeds are being imported in with the coir. Still it is the medium of choice for organic farmers.

If you have a well you already know this but it was interesting to me to learn that a well high in iron actually helps plants by providing this element that they need anyway. Slime bacteria that is associated with iron wells, however, is a dangerous health risk and the use of chlorine from household bleach to treat it counters this beneficial affect.

Much can be learned from a soil test provided by Perry Laboratory but If you choose to test your own soil for nitrogen, phosphorus and potassium, be sure your reagent powder is fresh, advised Cliff. Last seasons left over capsules are not reliable. Meters to measure pH are not very accurate either unless the soil sample is uniformly dry. You can contact Perry Lab at (831) 722-7606 or http://perrylaboratory.com

My thanks to Monterey Bay Master Gardeners who offer so much for the home gardener. You can call their hotline (831) 763-8007 for horticultural advice. Their next Master Gardener Training class starts in January 2012. Check out their fall newsletter for articles ranging from integrated plant management techniques for Light Brown apple moth control to the successes and failures this year in members own gardens to how bunny rabbits may be the cause of your plant losses.

 

Indicator Plants

If you’re like me you’ve caught a case of pre-spring fever. How can we help it when the flowering plums almost overnight are cloaked in bright pink blossoms and clumps of bright yellow daffodils turning their faces to the sun? If you have allergies, it’s no secret that every acacia in the county is blooming. It’s fascinating to mark time with events in the botanic world. There’s even a word for it- Phenology. Websites like USA National Phenology Network at http://www.usanpn.org/  offer lots of information on the subject.

When do they occur each year? Phenology is a real science that has many applications. In farming and gardening, phenology is used chiefly for planting times and pest control. Certain plants give a cue, by blooming or leafing out, that it’s time for certain activities, such as sowing particular crops or insect emergence and pest control.  Often the common denominator is the temperature.

Indicator plants are often used to look for a particular pest and manage it in its most vulnerable stages. They can also be used to time the planting of vegetables, apply fertilizer, prune and so on. Here are some common garden plants and what they indicate:

When daffodils begin to bloom, sow peas.
When dandelions bloom, plant spinach, beets and carrots.
When lilac leaves are the size of a mouse’s ear, sow peas, lettuce and other cool-weather crops.
When lilacs are in full bloom, plant beans.
Once lilacs have faded, plants squash and cucumbers.
When apple trees shed their petals, sow corn.
When dogwoods are in full bloom, plant tomatoes, peppers and early corn.
When bearded iris are in bloom, plant peppers and eggplants.
When locust and spirea bloom, plant zinnia and marigolds.

When forsythia and crocus bloom, crabgrass is germinating. When this happens the soil temperature at a depth of 4" is 55 degrees. Treat with a pre-emergent.
When crocus bloom, prune roses and feed your lawn.
Mexican bean beetle larvae appear when foxglove flowers open.

Record your own observations at  Project BudBurst at http://neoninc.org/budburst/index.php  to start a data base for our area. Another great site is National Sustainable Agriculture Information Service  at http://attra.ncat.org/index.php.  Sites like these can also help you design orchards for pollination and ripening sequence, design for bee forage plantings, design perennial flower beds and wildflower plantings as well as plantings to attract beneficial insects and enhance natural biological control. How cool is that?

Time to Prune Roses, Fruit trees and Flowering Shrubs

I’ll be the first to admit it’s hard to bundle yourself up to go out and work in the garden on a cold winter day. Bright sunshine sure helps but still it’s not t-shirt weather yet. It helps to think how good that fresh air will feel, not to mention that working in the garden relieves stress. And think about all that great exercise you get without getting on the boring treadmill.

Depending on your weight and how vigorous you work, one hour of gardening can burn up about 272 calories. Transplant a shrub, and the number of calories burned could jump to an incredible 340 calories per hour. Just think of that extra helping of potatoes-au-gratin you had over the holidays.

There’s plenty to do this time of year. Neaten things up by removing rotting perennials and sweep the leaves and debris off the driveway and your roof. 

It’s time to prune fruit trees and smother overwintering eggs and insects by spraying with horticultural oil. Combine your spray with lime-sulfur ( except on apricot trees ) to kill fungal disease spores like the ones that cause peach-leaf curl.  has also been shown to supress fungal diseases.You’ll want to do this again when the buds swell but before they open ( about Valentine’s Day )

Control large vines like overgrown honeysuckle, pink jasmine,  morning glory, passion vine, potato vine and trumpet creeper by radically thinning or even cutting back low to the ground if they are a big, tangled mess. Wait until after flowering to heavily prune spring-blooming vines such as wisteria.

Pruning Roses
When buds along rose canes begin to swell, prune repeat flowering roses by removing spindly or diseased shoots and dead wood. Do this before they start leafing out which wastes plant energy. Cut back the remaining stems by about a third, cutting canes at a 45-degree angle just above an outward facing bud. Don’t worry whether your pruning job is perfect. Roses are super forgiving and you can trim them up again later. You want to produce lots of roses not just a few of exhibition size. Aim for a vase-shaped  bush with an open center.

Prune old garden roses that bloom once in the spring after flowering.
Climbing roses require little pruning. Cut out extra stems if there are too many and also cut back long established canes to about the place where they are slightly thicker than a pencil. Then cut each side stem down to several inches. This will cause the cane to flower along its complete length for a beautiful spring display.

If any old leaves still cling to the plant, remove them. Rake up any debris beneath the plant and discard to eliminate overwintering fungus spores. It’s a good idea to spray both the bare plant and the surrounding soil with a combination organic horticultural oil to smother overwintering insect eggs and a dormant spray like lime-sulfur to kill fungus spores. If you usually have a problem only with black spot you can use a mixture of 1 teaspoon baking soda with a few drops of light oil in 1 quart water and spraying every 7 to 10 days.  Thoroughly coat the trunk, branches and twigs.

Other tasks to do in the garden in January:

Cut back hydrangeas if you haven’t already done so. Apply soil sulfur, aluminum sulfate or other acidifier if you want to encourage blue flowers.

Cut back summer flowering deciduous shrubs and vines.  Don’t prune spring flowering varieties like lilac, flowering cherry, plum and crabapple, rhododendrons, azaleas, camellias, weigela and spirea until after flowering or you can cut some during flowering to bring in cuttings for bouquets.