Category Archives: gardening tips

Watering Plants in the Summertime

All plants need water– even those that are tolerant of our summer dry conditions. Water makes up 90-98% of every plant we grow. It’s needed for photosynthesis, as well as reproduction and defense against pests.

What happens to a plant when the thermometer tops 100 degrees? Are there some plants that can survive tough times more easily?

Mimulus ‘Jelly Bean Gold’

Photosynthesis is one of the most remarkable biochemical processes on earth and allows plants to use sunlight to make food from water and carbon dioxide. At temperatures about 104 degrees, however, the enzymes that carry out photosynthesis lose their shape and functionality. A garden that provides optimum light and water but gets too hot will be less vigorous. Tomatoes, for example, will drop blossoms and not set fruit if temperatures are over 90 degrees. Plants that do endure hight heat may be stunted and weakened attracting pests and diseases even if water is available.

Plants have natural systems that respond to heat problems. Plants can cool themselves by pumping water out through the leaves for a kind of swamp cooler effect. They can also make “heat-shock” proteins which reduces problems from over heating. All these strategies can take resources away from a plants other needs like growth, flowering and fruiting.

California fuchsia

It’s no surprise that many California natives are adapted to high temperatures. Some California native plants that can handle the heat with little water include salvia, mimulus, California fuchsia, eriogonum, manzanita, artemisia, California milkweed, ceanothus, mountain mahogany, bush poppy, bush lupine, native penstemon, monardella, mahonia nevinii, fremontodendron and holly-leafed cherry.

Other well adapted plants that are known to be more tolerant of heat include butterfly bush, germander, rosemary, smoke tree, rudbeckia, coreopsis, lantana, plumbago, gaillardia, lilac, sedums, oregano and verbena.

So how much water do different types of plants need during the heat of summer?

Be sure that you water trees and shrubs deeply checking soil moisture first with a trowel. Established small to medium shrubs should be watered when the top 3-6″ is dry, large shrubs and trees when the top 6-12″ is dry.

As a rule of thumb, trees and large shrubs need deep but infrequent irrigation. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Bush Poppy

Apply water with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water district’s restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod that’s 1/4 inch – 3/8 inch in diameter into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly waterings to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on type.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy

April in the Garden in the Santa Cruz Mountains

Spring might have officially started mid-March but judging from the wonky weather it’s hard to tell. We did experience a “Miracle March”  with a pretty good dose of needed rainfall along with some very cold weather. You never know what to expect in March around here.

Sherman, my Welsh springer spanial, enjoying a spring day in Scotts Valley

But now we’ve turned the corner on spring with flowers bursting open within hours on these nice days. The Black-headed grosbeaks have returned to my yard for the breeding season. Like clockwork they show up on almost the exact day each year. It’s my version of the swallows returning to San Juan Capistrano.

Looking forward to the rest of spring, here’s what I’ll be doing around here in April.

Hopefully we’ll have plenty of April showers. This latest rainfall is surely  welcomed. One of the perks of a cool, rainy spring is that shrubs and perennials have longer to establish a good root system before hot weather arrives, ground covers have time to spread and shade the soil, conserving moisture come summer. What strategies can you follow that will make your garden low maintenance this summer and give you extra time to enjoy it?

Plant in masses. When designing or reworking your garden, make it

ajuga reptans, a groundcover for shady spots

easy on yourself by planting fewer varieties but in greater numbers. Planting this way will reduce the number of different maintenance tasks for that area. For example, if you have a large hillside that you want to cover, plant it with a groundcover like ceanothus gloriosus which fans out 6-15 feet. Some manzanitas like arctotaphylos uva-ursi eventually spread to15 feet each. Sage leaf rockrose and germander are also good for sunny areas. A shady spot could be planted with ajuga, creeping mahonia or Walkabout Sunset lysimachia.

Another time saving strategy is to group plants with similar moisture needs. This may sound like a no brainer but if you have just one prima donna in a bed of more drought tolerant plants, you’ll be dragging the hose over to that bed for just one plant or having to run your irrigation system more for it. If you find that some of your plants are not quite as low water as you’d like, move those to their own spot. In general, plants with large leaves usually require more water and transpire faster while drought tolerant plants typically have one of more of the following characteristics: deep taproots and leaves that are smaller, silver, fuzzy or succulent.

ceanothus ‘Carmel Creeper’ – A low maintenance, low water groundcover for sunny spots

Avoid putting thirsty plants in hard-to-reach places. If the irrigation system doesn’t reach that far, keep it simple by planting drought tolerant woody shrubs or perennials there.

Pluck weeds when the soil is moist and before they have gone to seed. Even if you don’t get the entire root of more persistent weeds, just keep pulling at the new growth. Eventually, the plant will give up having used up all of the food stored in its roots. I’m still battling hedge parsley with it’s sticky seed balls that will cling to my shoelaces and the dog’s fur if I don’t get it before it sets seed.

Plant edibles among your other plants near the kitchen. Tricolor sage looks great alongside other plants with pink and violet leaves. Purple basil planted below the silver foliage of an artichoke is another great combination. Lemon thyme growing next to a burgundy colored dwarf New Zealand flax would look spectacular, too. And don’t forget to plant decorative and delicious Bright Lights swiss chard with its stalks of yellow, orange, pink, purple, red, green and white throughout your beds. It’s one of the easiest vegetables to grow.

So get the lemonade ready to enjoy all your free time later this season.

How to Plant a Spectacular Container Garden

There’s something about a beautiful container overflowing with interesting flowers, foliage or succulents that always gets my attention and although I already have 241 containers I’m always on the lookout for ideas to create one more.

Wall planter with ivy geraniums

You can grow anything in a container. Think of them as furnishings. Grow herbs and other edibles near the kitchen door, fragrant flowers to attract beneficial insects, hummingbirds and butterflies, California natives or even plants that glow in the moonlight.

Some of the most dramatic containers utilize the concept of combining a thriller, some fillers and spiller or two. Not all my containers will use this formula but I seem to be drawn to those that do. Plants in nature can be quite random in the way they grow together and still be lovely. Containers need a bit more order to dazzle and direct the eye.

Thrillers act as the centerpiece of a container. They are usually big, bold and beautiful. Next come the fillers. Fillers can be foliage or flowering plants but they should complement and not overwhelm your largest plant. Usually they have a mounding shape and I’ll plant several around the thriller. The last plants are the spillers which are small and will soften the edge of the container.

When planting mixed containers never use more than three plant

Mixed container planting

colors, two is sometimes enough. That doesn’t count green unless it’s lime. Skimpy pots are a miss, pack the plants so the pots are full when you’re done. You want the pots to look good right away. Big pots, at least 16″ across are dramatic and make a nice contrast to matching smaller ones.

In choosing a container, remember a porous clay pot will dry out fast in the summer sun as will a small pot. If you want pots on a sunny deck, you’ll have better results if your container is made or ceramic or colored plastic and is big enough to allow 2 inches of potting soil around the root ball. I don’t use water absorbing polymer granules in my containers as they are all in shade in winter and would stay too wet depriving plant roots of oxygen.

Water when the top 1 inch of soil in the container is dry. On a very hot day, watering mid day will cool the soil although I like to get my watering done early. Get to know your plants. Plants that are still growing into their containers need less frequent watering than those that are getting root bound. How much water? Water until it runs out the bottom and empty the saucer the next day if any water remains. Use a gentle nozzle that doesn’t dislodge the soil or compact it. Also make sure the water in the hose isn’t hot from lying in the sun.

Plants in containers are watered frequently and the water draining out of the bottom carries away nutrients. Actively growing plants need regular feeding from spring to early fall. Water soluble fertilizers are fast acting. Dry granules and time release capsules last longer. Organic fertilizers tend to work more slowly and are especially ideal for trees, shrubs and long lived perennials or for large planters in which you keep the same soil from year to year. Be sure plants are moist before feeding. The best fertilizer is the one that you get out of the package and onto your plants.

June in the Garden-What to Do?

I didn’t get everything done in May that I had on my to-do list. Who ever does? Anyone who tends a garden knows how fast plants grow with the longer, warmer days and nights. So this month I continue to work on my own garden tasks as well as help others renovate their gardens to look great, support native pollinators, wildlife and habitat.

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.

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.

Pink rhododendron.

When the last flowers of your rhododendron, azalea, camellia, weigela and spirea have finished it’s time to prune them. If you prune too many months after flowering your risk removing the flower buds forming for next year. Basically it’s best to prune lightly each year to shape plants that have become too leggy. The rules apply to most plants. Prune to the next whorl or set of leaves. To increase rhododendron bloom next year, break off any faded flower trusses just above the growth buds being careful not to damage the new buds.

Swallowtail feeding on lemon

Apply the second fertilizer application for the year to your citrus and fruit trees. The final one for the season 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.

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.

Erysimum ‘Apricot Twist’

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.

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?

hedge_parsley_weed
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.

california_poppies
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.

hakonechloa_winter
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.