Category Archives: gardening tips

Tips for Planting Success

With our gardens coming to life at this time of year we are hopeful that each plant will achieve its full potential during this growing season. But that doesn’t always turn out to be the case and sometimes it’s hard to figure out what exactly is the problem. Growing plants isn’t an exact science. What works over at the neighbors yard doesn’t always apply to ours. What are the different factors that makes a plant thrive or just mope along? And how can you plan when one source shows the plant’s size at 6 feet tall while another has that same plant as 8-12 ft tall and just as wide? What’s a gardener to do?

Callistemon ‘Little John’

When designing a garden, whether it’s for a client or my own garden, I take into account the growing conditions such as soil type and fertility, winter low temperature, space and light. All plants need water to carry moisture and nutrients back and forth between the roots and leaves. Some need more water than others to do this but all have their own levels of tolerance. Too little or too much water can be harmful to your plant’s health.

Choosing the right plant for the right spot is another important factor. How do you determine if your garden has the right amount of sun or shade? In our area a good rule of thumb in deciding if your plant is getting enough or too much sun is to note how many hours of full sun, part sun or bright shade your area is receiving during the middle of the day. Too little light can make plants weak and leggy looking with few flowers or fruit.

Most plants enjoy morning or late afternoon sun. Winter conditions are not always as important as those of the summer. Then again if your area gets no winter sun and your soil is heavy clay that sun-loving native plant might not survive. Sometimes it’s complicated.

Grevillea lanigera ‘Mt Tamboritha’

Allow enough space for your plant to grow. Plants can become stunted without enough room to grow and overcrowded plants often get diseased when air doesn’t freely flow between them. There’s a difference in a plant that just needs a little time to kick in and really start growing and one that is not thriving. Be patient.

Plant your new addition correctly. Dig the planting hole at least twice as wide as the container but no deeper than the depth of the root ball unless the soil is deeply compacted. Leaving the bottom of the hole undisturbed helps prevent the plant from settling below its root crown. In soil containing a high percentage of clay, score the sides of the planting hole with a shovel to aid root growth outward from the hole.

It’s best not to add soil amendments or fertilizers directly to the planting hole, although it may be beneficial to spread some well composted manure to the surface before digging the hole. Wait until new growth is several inches long before applying fertilizer.

Planting a bit higher than the surrounding soil allows for a 2 inch thick layer of mulch around the plant but don’t bury the crown. After planting don’t till the soil again allowing the beneficial organisms to re-establish.

If you have a steep hillside, a super sunny or deep shade location or problem soil the above tips are even more important for your planting success.

November Tasks in the Santa Cruz Mountain Garden

Outside my window, the Forest Pansy redbud has started to display its spectacular orange fall color. There’s a suet feeder hanging from the branches so I get to enjoy the antics of the Pygmy Nuthatches, Purple Finches and the Chestnut-backed Chickadees all day long as I watch the changing colors of the foliage. Other than watch the birds and the changing foliage colors what should I be doing out there in the garden?

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Hedge parsley aka Torilis arvensis

Light weeding is easy now that the soil is soft and moist. The dreaded hedge parsley has germinated early with our October rains. With it’s spiny-ball seeds that stick to your dog’s fur and your socks it is not welcome on my property.  It’s invasive and a native of Europe. They’ll be easy to pull now.

Maybe I will plant a few more bulbs. The ground is cooling and there’s still plenty of time for them to receive adequate winter chilling. Come spring I’ll be happy I did.

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California poppies

I just planted wildflower seeds on my hillside. I hoping for more California poppies. I see some of last year’s wildflowers have reseeded. Nature knows when the time is right. I spread the new seeds in swaths and worked them very lightly into the soil, first hoeing off some early weeds that would compete with them.

What not to do in the garden now? I don’t need to prune trees and shrubs at this time of year. Other than clipping a few well placed branches to use for holiday decorations, I’m off the hook for this task. Deciduous trees are still in the process of losing their leaves and are not fully dormant. Evergreen shrubs and conifers can be trimmed lightly but most shaping is done when they start growing in late winter or very early spring. Fall is not a good time to prune. Wounds heal slowly, leaving them more susceptible to disease. As a general rule, don’t prune when leaves are falling or forming. To avoid sap flow on birches and maples prune after leaves mature next year.

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Japanese Forest grass in winter

The growing season is pretty much over for me except to enjoy what’s left of fall color and the ornamental grasses waving their seed heads in the wind. A lot of perennials are dying back but I’m not in a hurry to neaten things up. The seed heads left in the garden supply food for birds and other creatures while the foliage provides shelter for the plant in the cold and frost. Remove anything that has turned slimy or just plain unattractive but leave berries and seed heads for food and winter interest.

At this time of year my garden is visited also by Lesser goldfinches and warblers who will spend the winter and I’m doing them a big favor by not cutting back brown foliage containing nutrient-rich seed heads. Some of the reliable seed producers that I won’t have to clean up this weekend include artemisia, aster, coreopsis, penstemon, sedum, lupine, salvia, black-eye Susan, coneflower, phlomis, monarda, agapanthus and grasses.

Used to be the first frost in our area came about the first or second week of November but not anymore. Be prepared whenever it comes by moving frost tender plants under overhangs if possible or having frost blankets ready to cover frost tender plants.

Pruning Ornamental Grasses

Who doesn’t love a garden filled with the movement and beauty of ornamental grasses especially during the fall? But how do you take care of them after the show is over for the season?

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Lomandra and NZ flax in mixed planting

When I recently received an email asking what to do with an ornamental grass that had already turned that soft tawny color I figured it was time to brush up on how to care for them. To prune or not to prune? That is the question.

Grasses are distinguished from other plant families by their growth habit. They grow upward from the base of a leaf or shoot and can regrow from the crown when cut back. True grasses generally have extensive root systems which help control erosion. There are other grass-like plants like chondropetalum, New Zealand flax, kangaroo paw and lomandra that resemble grasses in their growth habits and are often some of the best companions for interplanting with grasses.

Most grasses require little care, minimal fertilizer and only occasional grooming. Some flourish with just enough water to meet their needs while others need regular irrigation. Diseases and insect pests are rare and they are not attractive to deer. They have succeeded because of their adaptability and have evolved to suit almost every environment and climate on earth.

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Japanese Blood grass – small and goes dormant

Basically, grasses and grass-like plants fall into 4 different pruning types: Large or small types that go dormant and large or small types that stay evergreen.

Large grasses that go dormant such as miscanthus and calamagrostis are pruned yearly in late fall to late winter. It’s best to hold off on pruning as long as possible to preserve the winter interest and to provide food for birds. When they turn brown and start shedding it’s time to prune. Gather the blades together with a bungee cord or rope and cut down to 10 inches.

Small grasses that go dormant such as Japanese blood grass or fountain grass should be pruned yearly at the same time. Don’t cut them too close to the crown or you risk losing a few clumps. Cut those under 3 feet tall down to 3 inches and those that grow taller down to 6 inches.

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The Guardsman- NZ flax large & stays evergreen

Large, evergreen grass-like flax and cordyline can be pruned anytime to cleanup and resize but rejuvenation should be done mid-spring. When pruning to freshen up the foliage, select the most damaged leaves and cut them out at the base. If your plant is overgrown or suffered winter damage, prune severely in mid-spring cutting off all the foliage at the base. Tall cordyline varieties can be cut off a few feet from the ground and they will re-sprout below the cut or from the base.

Lastly, small evergreen grasses like carex, acorus, blue oat grass and blue fescue grass can be cleaned up in spring by putting on rubber gloves and combing through the grass. If this kind of cleanup isn’t enough you can reduce the height by two-thirds and in a couple of months they will look good again.

What’s in your Soil?

“The soil is made of butterfly wings, dinosaur teeth, pumpkin seeds, lizard skins, and fallen leaves.
  Put your hands in the soil and touch yesterday, and all that will be left of tomorrow shall return
  so that new life can celebrate this day.”  -Betty Peck

Soil makes all the difference to the plants you grow. The biggest issue we gardeners face is the ongoing battle with soil. If yours is difficult to manage or just plain unproductive you’ll be disappointed like me with the performance of many of the plants you put in the ground. Even tough plants like California natives have soil preferences and they are not always what’s in your garden.

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Low water-use plant responding to fertile soil

We live on ancient sea cliffs.  Soils in Bonny Doon and Scotts Valley consist of shallow, excessively drained weathered sandstone and shale. Felton soils were formed from shale, sandstone or mica schist. Those in Ben Lomond and Boulder Creek had their beginnings from weathered sandstone or granite. Although these provide the necessary mineral component of our soil. organic matter or humus from decayed plant and animal material are necessary also for fertility.

Here’s why improving your soil will make a difference to the health of your plants.

Good soil-with both organic matter and minerals-helps plants grow by forming the food supply for soil bacteria that help make food available for plant growth. Most of a plants energy goes to producing substances that drip out through the roots to attract bacteria and fungi. These in turn attract good nematodes and protozoa to the root zone. The protozoa eat bacteria and the nematodes eat not only the bacteria but also fungi and other nematodes to get carbon. What they don’t need they expel and this feeds the roots much like earthworm castings.

Down in the soil, if a plant needs different foods it can change what is secretes. Different substances will attract different bacteria, fungi, nematodes and protozoa. This huge diversity of soil biota helps the good guys keep the bad guys in check.

A common way to destroy the microbiology of the soil is to add salts in the

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Collection of perennials one year after planting in amended soil.

form or non-organic fertilizers. The salts kill the bacteria and fungi by dehydrating them. Then the plant can’t feed itself and becomes dependent on its fertilizer fix. Without the good bacteria and fungi in the soil other parts of the food chain start dying off as well.

The soil food web is also responsible for soil structure. Bacteria create slime that glue soil particles together. Fungi weave threads to create larger soil particles. Worms and insects distribute bacteria and fungal spores throughout the soil and create pathways for air and water.

What can you do to bring your soil back to life?
• Mulch around perennials, shrubs and trees with 2-3” of compost, wood chips or other organic mulch.
• Apply mycorrhizal fungi, especially in a new garden that’s been rototilled or chemically fertilized. You can find this in most organic fertilizers and some organic potting soils.
• Try to avoid walking on the root zone of plants. This kills fungi in the soil. Install stepping stones to preserve soil structure.

Feed your soil- not your plants.

Late Summer Tasks for the Garden

It’s darker in the mornings now with the sunset coming earlier each evening. All that time I thought I’d have back in June to get things accomplished in the garden has vanished in what seems like a wink of an eye. Still the weather these days is perfect for being outside and pecking away at my to do list. There are also some late summer/early fall tasks that need attention.

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Alstroemeria ‘Rock & Roll’

Now through October, divide summer blooming perennials like alstroemeria, agapanthus, coreopsis, iris, daylily, yarrow, rudbeckia, calla lily, aster and penstemon that are overgrown and not flowering well. You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart although they don’t always bloom the first spring afterwards due to the energy they use re-establishing themselves. Start perennial flowers seeds now so that they will be mature enough to bloom next year.

This is the perfect time for transplanting or adding new plants to your garden. Why? Cooler air is kinder to plant foliage and soil temperatures are still warm which creates an excellent environment for new root growth. In the fall many plants and trees, even broadleaf evergreens, are entering a period of dormancy. With no need to allocate resources into foliage, plants are transferring all their energy into roots and storing nutrients for the cool months ahead. By spring, the new roots system should be well established.

Perhaps it’s time to remove or reduce lawn. Replant with more drought tolerant ornamental grasses or perennials.

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Achillea millefolium

Fertilize shrubs lightly one last time with an all-purpose organic fertilizer or layer of compost. This advice doesn’t apply to California natives. They like compost only around the roots during the winter while they get ready for their growing season.

Roses especially appreciate a bit of fertilizer now, encouraging them to bloom another round in the fall. 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 flower bud to grow much sooner than if you cut to one with only three leaves.

Plant cool season veggie starts like broccoli, cabbage, cauliflower, chard, lettuce, spinach, brussels sprouts, onions and leeks in soil enriched with 4-6″ of compost as summer vegetable crops will have used up much of your soil’s nutrients.You can sow seeds of beets, carrots, radishes, spinach, arugula, mustard and peas directly in the ground.

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Soil builder cover crop mix

If you aren’t going to grow vegetables in the garden this fall consider planting a cover crop like crimson clover, fava or bell beans after you’ve harvested your summer vegetables.

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

Spider 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.

And whatever you do, enjoy being outside in this beautiful place we call home.

Troubleshooting Plant Problems

Troubleshooting is a form of problem solving. And whether it’s a car problem, your smart phone, an irrigation system or yellowing leaves on a plant the goal is to solve it and make the product or process operational again. When you eliminate the potential causes of the problem hopefully the solution restores everything to its working order. Sounds like something Sherlock Holmes would say and it’s sometimes easier said than done as we all have experienced.

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sunburned heauchera leaves

A few weeks ago I received a text with pictures of some plants with brown spots and asked what I thought might be the problem with their plants. This was after the heat wave we experienced and after asking a few questions about irrigation, location and how long the plants had been in the ground, I determined that the plant leaves had been burned in a pattern consistent with the location of the beating sun. At this time of year plants are growing wildly and need a good soak moistening the entire root zone. The solution: Better to water deeply less often than lightly which might not reach all the roots.

The subject of how much fertilizer and what kind came up in another troubleshooting email thread between some fellow horticulturalists. The issue was whether to use another round of organic high phosphate fertilizer in order to encourage bud development on a notoriously short-season tree dahlia. After some lively discussion we decided that the early spring application of rock phosphate was sufficient. Sometimes adding too much phosphorus may actually hurt a plant by preventing the uptake of other nutrients which must also be available to the plant in order to prevent unexpected deficiencies to appear. A balanced fertilizer containing all three nutrients- nitrogen, phosphorus and potassium-was recommended for the remainder of the season.

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yellow leaves on lemon

Then there were some problems in my own garden. Well, it seems I am always trying to solve something with plants, pests or critters but this was with my lemon tree. At first I was perplexed when the older leaves of my lemon tree started turning yellow a couple months ago. The new growth looked fine so it wasn’t an iron deficiency where the young leaves display green veins along with the yellowish color.

It wasn’t a nitrogen deficiency either where the mature leaves slowly bleach to a mottled irregular green and yellow pattern, become entirely yellow and then are shed while the discoloration spreads to the younger leaves. I had fertilized in March with an all-purpose balanced fertilizer. Citrus are heavy feeders and require a steady source of nitrogen, the ideal citrus fertilizer having a ration of 3:1:1 (N:P:K)

After eliminating other mineral deficiencies or overwatering as the problem I decided that my lemon was simply dropping interior leaves which is normal after winter but I wanted to trouble shoot all potential causes to be sure citrus greening wasn’t the culprit. If it had been this deadly disease the leaves would have exhibited an asymmetrical pattern.

To quote Sherlock Holmes “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.” I’ll try to remember that when I’m troubleshooting my next problem in the garden.