Category Archives: gardening tips

Keeping Gardening Facts Straight

I?ve gotten several emails lately requesting more information about something mentioned in a recent column. I also received a phone call from a reader describing a bad encounter with a certain common plant. She wanted to share her experience so it didn?t wouldn?t happen to anybody else. And a conversation about how bad the poison oak is this year triggered a discussion about how to dispose of the stuff. So here goes. All the news that?s fit to print.

Whether it was Joe Friday who said it or Dan Akroyd in the Dragnet parody. we all want ?Just the Facts, Ma?am?.

chipped_bark
ramial bark chips

In my column a couple weeks ago about garden planning for the drought, it was the last line ?And don?t forget the? mulch (no shredded bark, please)? that caused a bit of confusion. It?s great that everyone has accepted the value of covering the soil with organic mulch. Organic mulches- such as bark chips, treated sawdust, straw or even grass clippings- keep plant roots cool, encourage earthworms and other beneficial organisms, conserve soil moisture, combat weed growth and protect the soil from erosion.

But is there an organic mulch that is better than another?

There are many types of mulch available. Nurseries sell different types of mulch in bags, building supply yards carry everything from bark nuggets in different sizes to treated sawdust to chipped bark and even shredded redwood bark. It?s the shredded redwood bark, also called gorilla hair, that does nothing for the health of your soil. If you have a very steep slope you may have to go with this type of mulch but that?s the only time I can recommend it. It will cling to a hillside without washing down in winter rains but treated sawdust would also work for this type of terrain and is much better for soil health.

Of all the types of organic mulches out there, recent studies have shown that ramial bark chips are one of the best mulches to improve soil health. Ramial chips come from trees and brush with branches up to about 3? in diameter with or without leaves. 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 a tree?s 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 soil scientists, G.Lemieux and R.A.Lapointe. You can obtain these kind of chips free from tree trimming companies who are probably working nearby chipping roadside brush for PG&E.

euphorbia2
Euphorbia

About that call from a reader who had a terrible experience after pulling some plants in her yard that had gotten a little out of hand. She said she and her husband ended up with severe eye burn after getting some toxic sap from euphorbia in them. She said they really don?t know if some of sap became airborne while they were pulling stems or if they accidentally rubbed some near their eyes at some point in the day. They went to Urgent Care right away for treatment but the pain lasted for days. She described it as one of the most painful experiences she has ever had. Euphorbias are very deer resistant and drought tolerant and are being used more and more in gardens.

Many of us, me included, grow tropical milkweed or Asclepias curassavica to attract monarch butterflies. The milky sap from this plant protects the monarch from being eaten and can cause the same painful burning of the eye. I read of a case where a gardener?s clothes brushed some stems while she was tending the garden. Later she wiped the sweat out of her eyes and didn?t realize she had also touched her pants. She ended up with cornea burn causing temporary blindness and had to take strong pain relievers and steroids to elevate the pain.

poison_oak
Poison oak

Lastly, a fine crop of poison oak is growing this year so thick in places you can barely avoid it. The new foliage literally glistens with toxic oils. Many birds relish the white berries that form later in the season. 9 out of 10 people will get a rash if even one drop of urushiol oil touches the skin. And this oil has lasting power. It can stay active on any surface, including dead plants, for up to 5 years. Burning dead or dormant poison oak branches is especially dangerous as urushiol oils released in smoke can produce disastrous results if inhaled. So what to do with the stuff if you pull it out? Do not put it in your green waste can. It can end up being ground into mulch along with other green waste. Instead put it in your gray garbage can. Other plant matter that has to be put in the garbage can is pampas grass and bamboo. Don?t put them into green waste

So that?s the skinny on shredded redwood or gorilla hair, common plants with toxic sap and poison oak disposal. Be careful out there.

The Garden of Our Dreams vs The Real World

polygala_Petite_ButterflyWith our gardens coming to life at this time of year we are hopeful that each plant will achieve its full 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 neighbor’s yard doesn?t always apply to ours. What are the different factors that can make a plant thrives or just mope along? And how can you plan when one ?reliable? plant source says the plant will get 6 ft tall an another shows that same plant as reaching 8-12 ft tall and just as wide?

When designing a garden whether it?s a client?s or my own I need to take lavender_West_Zayanteinto account the growing conditions such as soil type, nutrients, water requirements, high and low temperature, space and light. Most all plants use 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 or nutrients can be harmful to your plant?s progress.

Healthy soil provides an anchor for plant roots and helps support the plant in addition to providing nutrients. Healthy soil contains micro organisms and adding organic matter to your soil when you plant and in the form of mulch will increase your soil?s fertility.

Choosing the right plant for the right spot is another important factor but how can you determine if your garden has the right amount of sun or shade or moisture? In our area a good rule of thumb in deciding if your plant is getting enough or too much sun is to look up during the growing season and see how many hours of sun, part sun, bright shade or partial shade your area is receiving. To simplify, it?s not as important what is going on during the winter but knowing the summer conditions is crucial. Too little light can make plants weak and leggy looking with few flowers or fruit.

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. When digging the hole be sure that you loosen surrounding soil 2-3 times the width of the root ball. There is no rule that you can?t loosen the soil even wider around your planting hole. Use the shovel to loosen the edges of the hole so that it?s not hard and smooth. Roots have an easier time of growing out from the initial hole is sides aren?t hard as a rock. You can loosen the soil below the depth of the root ball if it?s really hard and amend it also. Be sure to firm the soil underneath the plant so the crown of your plant doesn?t sink below grade and drown during winter rains or watering. Planting a bit higher than the surrounding soil also allows for a 2? thick layer of mulch.

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

The November Garden

Cercis_Forest_PansyOutside my window, the Forest Pansy Redbud has started to display its spectacular burnt 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. Out back I have a Catawba Crape Myrtle also starting to show fall color. Its leaves are turning a rich butterscotch shade which is lovely but not the reddish-orange described in the books. What causes fall color to vary from plant to plant? How does location in the garden, weather, climate and growing conditions affect what you see each fall?

The brilliant fall color we see in the leaves of trees and plants is always there. It?s just masked by Japanese_Maple-fall_color.1280chlorophyll during the growing season as the plant is busy making food while the sun shines during photosynthesis. Come autumn, shorter days and cooler temperatures cause the trees to switch into energy-storage mode, at which point their leaves stop producing chlorophyll. For the few weeks before the leave fall to the ground, they are colored only by their natural pigments. It’s these colors – red and purple anthocyanins and yellow and orange carotenoids that make fall foliage so glorious.

Some years the show is more dramatic than others. The best conditions for intense leaf color to develop are dry sunny days followed by cool, but not freezing nights. A warm, wet autumn will almost surely result in less-than-spectacular foliage because the process of chlorophyll loss will be less consistent. Freezing temperatures or winds meanwhile can cause leaves to drop suddenly denying them opportunity to enter their slow, colorful dormancy. Finally, trees that are under stress because of pests, disease, injury or drought may drop their leaves with no color change at all.

Japanese_Maple-fall_color2.1280So if your garden becomes shady early in the fall this may result in less vivid fall foliage. If your trees are stressed by drought like this year you may not get the usual colorful fall display. These and the above factors all affect the intensity of fall foliage colors.

Now is a good time to shop for plants and trees that can punch up the color of fall in your garden. Seeing your new addition in person will show you exactly what color you are going to get. Sure Autumn Gold Ginkgo will probably always color up bright yellow and Sango Kaku Japanese maples will show off their characteristic golden foliage but the fall color of Purple Smoke Bush, Katsura tree, Witch Hazel, Pomegranate, Oakleaf Hydrangea and Blueberry, to name just a few, can vary.

First Frost
I received an email from someone new to the area about when to expect our first frost. I’ve kept a weather Japanese_Maple_Sango-Kaku_fall_color.1600journal since 1992 and based on my records occasionally we get a light frost at the end of October. Mostly though, the earliest frost has occurred about second week of November with late November being the most common. Be prepared by moving frost tender plants under overhangs if possible or having frost blankets (not plastic) ready to cover delicate plants.

Transplanting in Fall
Need to move a plant or install plants out of containers and into the garden soil? Now through February offers the best time to do this. Soils are still warm at this time of year which helps new roots get established quicker than in later winter.

Prepare the new location first before excavating any plant. Dig a hole twice as wide as the rootball, but just the same depth. Use a sharp spade to make clean cuts through roots. Cut roots will form new, dense and healthy roots.

Before replanting, especially from a container, check for roots that have circled the interior of the pot. These must be tugged loose and straightened when planted. Don’t be shy about loosening roots. When replanting be certain to keep the rootball at the same level it was and don’t add soil over the rootball. Most plants need oxygen at the soil level.