on propagating Abelia

How would you propagate Abelia x grandiflora?

According to the American Horticultural Society’s Plant Propagation
edited by Alan Toogood (DK Publishing, 1999), Abelia may be propagated
from softwood cuttings in spring, from greenwood cuttings in late spring,
and from semi-ripe cuttings in early to late summer. “Cuttings… root very readily in a closed case or mist bench. Softwood cuttings from the first flush of root growth in 2-4 weeks. In colder regions, do not pot greenwood cuttings taken after midsummer; prune cuttings into a bushy habit, but allow new growth time to ripen–if not well established, they overwinter badly. Keep semi-ripe cuttings taken in late summer
frost-free. Plants flower in 1-2 years.”

Here are links to general information on propagation from cuttings:

Plant Propagation by Stem Cuttings: Instructions for the Home Gardener, from NC State University

Propagating Plants from Stem Cuttings, from Rainyside Gardeners

yellow houseplant mushroom called Leucoprinus

I have a potted plant with a fungus growing in the soil. It
is bright neon yellow and grows like a mushroom, but with no cap on top.
The plant is in the basement near a window. The soil is damp and I’ve
avoided watering for awhile to let it dry out. What do you think the
growth is, how to get rid of it, and will it be harmful to my plant? I
keep plucking them, but they grow back.

I have had questions about the yellow houseplant mushroom before, and I
am guessing you are seeing the same thing. It is called Leucoprinus
birnbaumii.

Michael Kuo’s website, MushroomExpert.com has information about Leucoprinus. Excerpt:

“This little yellow mushroom and its close relatives are the subject of
many frantic e-mails to MushroomExpert.Com, since it has a tendency to
pop up unexpectedly in people’s flower pots–even indoors! The brightness
of its yellowness exhibits some rebelliousness, but it often creates a
striking contrast to the green houseplants that surround it.

“Leucocoprinus birnbaumii won’t hurt you, unless you eat it. It won’t hurt
your plant. It won’t hurt your pets or your children, unless they eat it.
There is no getting rid of it, short of replacing all the soil in your
planter (and even then it might reappear). Since it makes such a
beautiful addition to your household flora, I recommend learning to love
it–and teaching your children to love it, too.

“You might also impart the idea that mushrooms are very, very cool–but
shouldn’t be eaten. Perhaps your child would like to become an awesome
and famous mycologist some day. I would love to encourage your child’s
interest in mushrooms by putting his or her drawing of Leucocoprinus
birnbaumii on this Web page (at least temporarily).

“Leucocoprinus birnbaumii is probably poisonous; do not eat it. Handling
it, however, won’t hurt you.”

planting under a sycamore tree

We have a very large beautiful sycamore in our back yard. My roommate
thought it would be nice to build a flower garden around the base of the
tree, but something tells me that doing so would be harmful to the tree’s
root system. Is this true? I would love to hear your thoughts.

I think it should be safe to plant
shallow-rooted, shade- and drought-tolerant perennials and small bulbs
under your sycamore (I’m assuming you mean Platanus species, and not
sycamore maple, which is Acer pseudoplatanus). You just need to be
careful not to pile soil on top of any exposed roots, and try not to
scrape or scuff any roots when you are planting. This tree does have
spreading roots so they may extend out some distance.
More information about the tree can be found on the pages of the U.S. Forest Service.

Some of the plants which may work well in your garden are:

Lamium (but not the invasive Lamium galeobdolon)

replacing grass with moss in the garden

Could you tell me how to replace grass with moss in the shady areas of our lawn?

There are a number of options for replacing the grass in the shady part
of your garden. Should you decide to cultivate moss, Oregon State University’s page (now archived) on Encouraging Mosses should be of interest.

There are two books I would recommend, Moss Gardening by George Schenk
(Timber Press, 1997), particularly the chapter on “Moss Carpets,” and How
to Get Your Lawn Off Grass by Carole Rubin (Harbour Publishing, 2002).
Rubin gives directions for preparing your site, which involve digging out
existing plants or smothering the lawn with mulches of
leaves (12 inches), bark (3 inches), or newspaper (10 sheets thick).
Schenk offers several different methods for creating a moss garden.
Briefly paraphrasing, these are:

Work with nature, allowing self-sown spores of moss to take hold.
(Prepare the site by weeding, raking, and perhaps rolling the surface
smooth).
Encourage the moss in an existing lawn by weeding out grass. You can
plant what the author calls “weed mosses” which will spread, such as
Atrichum, Brachythecium, Calliergonella, Mnium, Plagiothecium,
Polytrichum, and others.
Instant carpet: you can moss about 75 square feet if you have access
to woods from which large amounts of moss can be removed legally.
Plant moss sods at spaced intervals (about one foot apart) and wait
for them to grow into a solid carpet.Choose plants that match your soil
and site conditions.
Grow a moss carpet from crumbled fragments. This is rarely done, and
only a few kinds of moss will grow this way, including Leucobryum,
Racomitrium, and Dicranoweisia.

In her book Big Ideas for Northwest Small Gardens, Marty Wingate
recommends Mazus reptans. It is semi-evergreen to evergreen with tiny
blue flowers from late spring through summer. It takes full sun to part
shade and is delicate looking, but takes foot traffic. It requires some
fertilizer to stay perky. Another source of ideas is the website www.stepables.com. Click on “plant info,” then
“plant search.”

Another ground cover that can take foot traffic is Leptinella gruveri
“Miniature Brass Buttons.”

propagating Hoya bella

Do you have any information on how to propagate Hoya bella?

I consulted The American Horticultural Society’s Plant Propagation (ed. Alan Toogood, DK Publishing, 1999) for information on propagating Hoya. This plant can be propagated by seed in spring or summer, and by cuttings, from spring to summer.

If the seeds are sown fresh and kept moist at 70-81 degrees, they should germinate in a few days. It is more common to increase this plant by cuttings. Cut a length of stem just below a leaf node. The cutting should be 3 to 4 nodes long. Dip its base in rooting hormone (which will also help stop the ooze of sap). Root as you would a stem cutting–fill a pot with a medium of fine grit (top 1/4 of pot) layered on top of gritty cactus soil mix (bottom 3/4 of pot). Gently push the cuttings through the fine grit into the soil mix. Keep slightly damp, but not too humid. If it is not warm enough in your home, provide gentle bottom heat to 70 degrees. They should root in 2 to 6 weeks. New plants will take a year or two to flower.

encouraging moss growth in the garden

What is the best way to encourage moss to take over and cover large surface areas in a relatively short amount of time? My goal is to replace my lawn with a moss garden.

Here are some links to information which may be useful to you:

Primitive Plants: Bryophytes, Ferns, and Fern Allies

Moss cultivation:

Encouraging Mosses

Mad About Moss: The Simple Art of Moss Gardening

There are two books I would recommend, Moss Gardening by George Schenk (Timber Press, 1997), particularly the chapter on “Moss Carpets,” and How to Get Your Lawn Off Grass by Carole Rubin (Harbour Publishing, 2002). Rubin gives directions for preparing your site, which involve digging out existing plants or–in your case–smothering the lawn with mulches of leaves (12 inches), bark (3 inches), or newspaper (10 sheets thick). Schenk offers several different methods for creating a moss garden. Briefly paraphrasing, these are:

Work with nature, allowing self-sown spores of moss to take hold. (Prepare the site by weeding, raking, and perhaps rolling the surface smooth.)
Encourage the moss in an existing lawn by weeding out grass. You can plant what the author calls “weed mosses” which will spread, such as Atrichum, Brachythecium, Calliergonella, Mnium, Plagiothecium, Polytrichum, and others.
Instant carpet: you can moss about 75 square feet if you have access to woods from which large amounts of moss can be removed legally.
Plant moss sods at spaced intervals (about one foot apart) and wait for them to grow into a solid carpet. Choose plants that match your soil and site conditions.
Grow a moss carpet from crumbled fragments. This is rarely done, and only a few kinds of moss will grow this way, including Leucobryum, Racomitrium, and Dicranoweisia.

Another approach is to change the soil pH. Sulphur should be beneficial to moss and detrimental to lawn grass. The reason for this lies in the fact that moss grows best with a soil pH of 5.0-6.0, while lawns grow best with soil pH between 6.0 and 7.0 (according to The Lawn Bible by David Mellor, 2003). Added sulphur lowers the soil pH, creating a more acidic environment.

managing caterpillars on apple trees

I have a question regarding apple trees and the caterpillars.

We have a great apple tree, that I have just noticed has the early nest of these crazy caterpillars that we get around here. Can you help me with the most effective way to get rid of these things before they hatch and start eating our tree???? Is spraying ok for the fruit??

It is possible that your apple tree has an infestation of tent caterpillars, but without seeing the pests, I could not say definitively. If this is what you have, the information below from Washington State University Extension should be of use.

Also, check out Toxic-Free Future’s page on managing tent caterpillars.
You should be able to prune out the affected part of the tree and dispose of the nest.

all about Verbascums

I would like to know a little more about Verbascums. Are they a biennial? Will they reseed themselves? How long a period will they bloom. How tall can they become? Are they invasive? Thank you for you help! I have had very little experience with annuals and biennials.

Verbascum includes 360 species, most of which are biennials, with a few annuals, perennials, and small shrubs, some of which are evergreen or semi-evergreen. The flowers grow on tall upright stems, and while individual flowers are shortlived, there are many of them and they bloom over a long period of time (summer into early fall, in most Seattle gardens).

In my own experience, they can reseed themselves, so if you would prefer not to have your plants do this, just cut off the tall stalk after the flowers have bloomed, and before they set seed. I checked the list of Washington State Noxious Weeds, and did not find Verbascum there, though it can be invasive in other parts of the country (Hawaii, for example).

If you would like information about specific varieties of Verbascum, the Royal Horticultural Society A-Z Encyclopedia of Garden Plants has photographs and descriptions of many of them.

lawn alternatives and planting under pine trees

Our house is on a corner lot. The side yard has a very small slope with big rocks along the edge. Presently it has a variety of flowers such as lavender that bloomed last summer.
However, my question is what kind of ground cover can I put there, other than grass, that would look good and be evergreen.

Secondly, there are two big pine trees at the corner. What are my options for plantings beneath these trees that would give it a pulled-together look?

I am guessing that the spot receives a good amount of sun, since you have lavender Lavandula that flowered there in the summer. Were you looking for a groundcover that will tolerate people walking on it, or did you want somewhat taller plants that will blend well with the lavender?

If you plan to walk on the area, you might want to consider chamomile (Chamaemelum nobile) or creeping thyme (Thymus serpyllum).

There are many great choices for plants not intended to be walked on, and I recommend that you take a look at some of the resources we have in the Miller Library so you can find the plants that most appeal to you. I recommend the books Gardening with Groundcovers and Vines by Allen Lacy (HarperCollins, 1993), and Perennial Groundcovers by David MacKenzie (Timber Press, 1997) as starting points.

Plants that are evergreen (or ‘ever-grey’) and might go well with lavender are Santolina, Helianthemum (sun rose), Teucrium chamaedrys (germander), and Ceanothus thyrsiflorus (creeping blue blossom ceanothus).

For the spot under your pine trees, you will need plants that tolerate shade and do not have large root systems. I would try Lamium (dead nettle), which comes in several foliage and flower colors, and I would avoid Lamium galeobdolon, a species which is considered a noxious weed in King County. Vinca (periwinkle) might also work. The Lady Bird Johnson Wildflower Center has information on planting beneath pine trees.

adjusting pH in hydroponic systems

What are the disadvantages of using white vinegar to lower the pH in my hydroponic system?

I have read that I should use phosphoric acid. But I have also read that phosphoric acid could be bad for hydroponic systems with hard water. I am using well water with a starting pH just below 8.

I also heard that nitric acid would be good for hard water but that the acid may be too aggressive for most novice users.

Here is general information on growing hydroponically from Virginia Cooperative Extension:

Hydroponically grown plants must obtain all their nutrients, including trace elements, from the nutrient solution. Success or failure may depend on precise and complete fertilizing practices. Complete nutrient solutions, specifically made for hydroponics, take the guesswork and the mess out of mixing one’s own formulas. All hydroponic nutrient solutions must be changed after a short period since evaporation causes concentration of salts in the water. Adding fresh solution to old solution would only make things worse. During spring and summer, pour spent nutrient solution around trees and shrubs.

Here is information from www.oswego.edu on adjusting pH in your hydroponic solution:

* The pH value refers to the acidity or alkalinity of the nutrient solution.
* pH readings run from 0 to 14 (0-6 acidic; 7 neutral; 8-14 alkaline).
* The recommended pH level for a general hydroponic solution is between pH 6 and pH 6.5. (Nicholls, 63)
* Many different variables can effect the pH level.

o Temperature
o Amount of light
o Evaporation
o Tap water refining
o Amount of nutrients

* With this amount of variables, periodically checking the pH level of the solution is vital to maintain a healthy environment for the growth of the plant

* Adjusting the pH level of the nutrient solution can be done simply.

o If a solution is too acidic, add one tablespoon of baking soda to three gallons of solution.
o If a solution is too alkaline, add one tablespoon of white vinegar per four gallons of solution.

This link to Texas Agricultural Extension Service addresses growing vegetables hydroponically, and offers details about nutrient solutions:

The book, Home Hydroponics…and How to Do It by Lem Jones (Crown Publishers, 1990) suggests testing the salt content of your water. Since you are using well water, you would need to contact the State Water Board (here is a link to Department of Ecology’s Water Resources page).

If the total amount of dissolved salts in your water is less than 700 ppm, the water should present no problem. This same resource says that a pH of 5.8 to 6.2 should be good for most plants. Since your pH is alkaline, you will need to acidify the solution. For adjusting a few gallons of solution, two regular aspirin per gallon of water will lower a pH of 8.0 to near 6.0. You can use a teaspoon of white vinegar per gallon as an alternative method. In a large system, this book recommends using sulphuric acid, but protect yourself from acid splashes and always pour the acid into the water and not the water into the acid.

The book Hydroponics for the Home Gardener by Stewart Kenyon (Key Porter Books, 1992), confirms the above, but remarks that vinegar is only a temporary measure and its effects will not hold for more than a few days. The author recommends using phosphoric acid, which he says is nearly harmless–just be sure to wash any spills off yourself right away with baking soda and water. If you add 0.1 millilitres of phosphoric acid per one gallon of water with a pH of 8.0, and a hardness factor of 136 parts per million, the pH should be reduced to 6.8.