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Search Results for ' Compost'

PAL Questions: 11 - Garden Tools: - Recommended Websites: 3

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Keywords: Coffee, Compost

PAL Question:

I have a composting question: I work at a large hospital and would like to collect all of the used coffee grounds/filters from the countless pots throughout the hospital and use it (tons of it!) for compost. Could you create adequate compost with just coffee and probably straw to balance it?

View Answer:

The information below is quoted from an article by Bob Smith, Washington State University Master Gardener Program Manager, Thurston County, in The Gardener, Vol. 6, No. 4, Winter 1995-96):

"In 1995, three local coffee houses called WSU Extension in Thurston County [Washington] for advice on composting coffee grounds. With the exception of worm bin composting, we were unable to find much information. Our Master Composter and Master Gardener volunteers decided to experiment. They composted about 270 pounds of coffee grounds donated by local espresso bars. They fed roughly 60 pounds to worms while composting the rest in regular bins.

"If coffee grounds are not worms's food of choice, they certainly must be high on the list. In appreciation for a meal of ready-to-consume grounds, the worms produced excellent compost. Incorporate coffee grounds soon after brewing into your worm box. This reduced the possibility of the grounds souring and attracting pesky fruit flies.

"We also experimented by composting coffee grounds in three types of traditional bins:
1) an enclosed holding bin made of recycled plastic,
2) a three-level wire stacking bin, and
3) a large, round, wire holding bin. Our primary concern was whether the coffee grounds would attract pests.

"We incorporated the grounds over a four month period yet experienced only one problem: fruit flies showed up in the enclosed plastic bin almost immediately after we added coffee grounds. In open wire bins, the grounds tended to dry out quickly. Overall, though, we found coffee grounds easy to work with and satisfactory for composting.

"Coffee grounds have a carbon-to-nitrogen ratio of 20:1, roughly equivalent to that of grass clippings. After brewing, coffee grounds contain up to 2% nitrogen. For composting purposes, consider coffee grounds green material similar to grass clippings. For brown material, we used leaves and sawdust. In these trials, we used a formula of one part green material (coffee grounds alone or mixed with grass clippings) to two parts leaves, or four parts green material to one part sawdust."

In the Winter 2009 issue of Master Gardener, WSU Extension Horticulturist Linda Chalker-Scott recommends using a thin layer (half an inch or less) of coffee grounds as mulch, topping this with a thicker layer (4 inches) of coarser organic material such as wood chips. She also says that the optimal percentage of coffee grounds in total compost volume should be 10 to 20 percent, and no more. The pH of spent coffee grounds varies, and one cannot assume they are acidic.

Season All Season
Date 2007-12-06
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Keywords: Mulching, Compost

PAL Question:

Can you give me some good sources for information about mulching and different mulching materials?

View Answer:

Below are many links to information about mulch, including several from Pacific Northwest government agencies. Explore these sites for lots of other useful information about gardening! There are also many helpful books on the subject, such as Mulch It! by Stu Campbell (Storey Books, 2001) and the Brooklyn Botanic Garden's guide, Healthy Soils for Sustainable Gardens edited by Niall Dunne (2009).

Brooklyn Botanic Garden has an excellent introductory article by Janet Marinelli entitled "The Dirt on Mulch", published in Plants & Gardens News, Volume 22, Number 2, Summer 2007.

ABOUT MULCH, types, and uses--Cornell Cooperative Extension (NY)

King County (Washington) Solid Waste Division mulch info
Make the mulch of it!

INFORMATION FROM THE PACIFIC NORTHWEST (generally useful)
-- Saving Water Partnership (Seattle)
--King Conservation District (Washington), manure share program

COMPOSTING COUNCIL OF CANADA:
Compost.org

MULCHING TREES AND SHRUBS
--North Carolina State University:
Mulching Trees and Shrubs

Season All Season
Date 2008-01-03
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Keywords: Soil amendments, Mulching, Compost

PAL Question:

Help! My clay soil is stunting the growth of my plants. I've amended the soil with compost and manure. Is there a another method of conditioning the soil that you can recommend?

View Answer:

First and most important, it appears mulching is the best organic solution for conditioning clay and heavy soils. Organic soil conditioners include compost, well-rotted animal manures, and natural fertilizers. Planting green manures such as clover, rye grass, or vetch are also effective for breaking up large clods in clay soil over time.

Sheet composting - laying compost over the entire area to be worked and using a fork (or rototiller) to work it into the soil to a depth of 2-4 inches - is cited by the resources listed below as an efficient method of soil conditioning. Both books listed below recommend repeating this process at least twice a year, in early spring and in late fall.

Secrets to Great Soil [by Elizabeth P. Stell, 1998, (pbk)] and
The Gardener's Guide to Better Soil [by Gene Logsdon, 1975, (pbk)]

The Saving Water Partnership (the City of Seattle and other government entities) has a website full of information about improving soil.

The site includes Growing Healthy Soil.

Current thinking contradicts the notion of working compost or other amendments into the soil, as explained in this March 31, 2010 Garden Professors blog post by Professor Linda Chalker-Scott of Washington State University Extension Horticulture. She specifically takes issue with the "Growing Healthy Soil" information linked above. Here is an excerpt:
"Not only will extensive digging or rototilling destroy any soil structure you might have, it will also take out the roots of any desirable plants in the vicinity). [...] improper soil amendment can cause serious problems such as soil subsidence, perched water tables, and nutrient overloads. This last point is especially important to anyone living near aquatic ecosystems, since excess nutrients always end up in the water. Before you plant this year, find out what your soil needs before amending it. And remember that mulching is the natural (and sustainable) way to add organic matter to the soil.

Season All Season
Date 2006-12-08
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Keywords: Trifolium, Pisum, Vicia, Cover crops, Grain, Garden fertilizers, Legumes, Vegetable gardening, Compost

PAL Question:

We plan to put in a vegetable garden next spring where we now have grass. It is a great sunny spot that we think would work well for this. The question is, after we cut out the sod this fall, someone has suggested we plant rye grass for the winter, is this a good solution? If not, what do we do to the soil this winter? (We plan to bring in some top soil after we take out the sod).

View Answer:

There are several approaches that you can use to get your new garden ready. One is from Growing Vegetables West of the Cascades by Steve Solomon. He recommends removing the grass, covering it with no more than 1/2 inch of completely rotted compost or 1 inch of raw ruminant manure, and spread agricultural lime at 50 pounds per 1,000 square foot. Do this in early October. Then scatter small-seeded fava bean seed at 6 to 8 pounds per 1,000 square feet. Rototill no more than 2 inches deep and relax until May. In late May you rototill deeply and or spade in the overwintered garden area. Then you can plant.

Another information source, Seattle Tilth's Maritime Northwest Garden Guide, recommends using an annual winter cover crop to improve the soil. It suggests using 85% legume and 15% grain for maximum nitrogen fixation. For the legume, you can use Field peas, Crimson clover, Fava beans or vetch. For the grain you can use cereal rye, winter wheat, spelt or barley. Most of these are applied at about 2 pounds per 1,000 square feet. Again you would rototill or turn under the cover crop in late April or May.

Solomon's method will provide a better total approach. You also should consider having your soil tested to find out what is missing and what your pH level is.

Season Spring
Date 2008-03-27
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Keywords: Juglans, Compost, Allelopathy

PAL Question:

Will black walnut leaves cause compost to be allelopathic? Should they be kept out of compost? Or is this folklore? The specific compost is made with chicken manure (fresh), grass clippings and walnut leaves. Are there plants that tolerate the toxin in black walnut?

View Answer:

It seems that the main source of toxicity is the roots of the walnut tree, rather than the leaves or shells. However, there are still those who believe that there is enough juglone in the leaves that they should be fully composted before use in the garden. Below are excerpts from information published online in various university extension websites, by various authors, and now unavailable:

"This toxic affect on surrounding plants appears to be related to root contact, as walnut hulls and leaves used as mulch have not shown toxic effects on plant growth. [Warning- Frank Robinson disagrees.] Because Walnut roots do not occupy the surface layers in most soil, many shallow rooted plants growing under walnut trees don't come in contact with the roots and are not affected by them." [Michigan State University]

"You've probably always heard that you should never add black walnut sawdust [or wood chips] to the compost pile because the juglone will kill everything that grows in the compost. Abraham says that's not necessarily true; that juglone is not found in walnut saw dust or wood chips. Nor do dead walnut trees exude juglone. Juglone is harmless to humans so you can go right ahead and safely eat fruit and vegetables grown near walnuts."[Katy Abraham]

"Robinson doesn't agree on the use of walnut residue in composting. He has this to say about black walnut saw dust, husks and leaves affecting plants. 'Tomatoes growing in clean soil in pots were severely stunted when leaves and nuts fell into the pots while we were on vacation. I know what juglone can do. I have seen a 15-year-old rhododendron killed a few weeks after its owner mulched it with black-walnut husks, and roses injured by an application of compost containing black-walnut sawdust.'" [Robinson]

"The juglone toxin occurs in the leaves, bark, and wood of the walnut but these contain lower concentrations than the roots. Juglone is poorly soluble in water and does not move very far in the soil. Walnut leaves can be composted because the toxin breaks down when exposed to air, water and bacteria. The toxic effect can be degraded in two to four weeks. In soil, breakdown may take up to two months. Black walnut leaves may be composted separately, and the finished compost tested for toxicity by planting tomato seedlings in it. Sawdust mulch, fresh sawdust or chips from street trees prunings are not suggested for plants sensitive to juglone, such as blueberry. However, composting of bark for a minimum of six months provides a safe mulch even for plants sensitive to juglone." [Ohio State University]

"To be on the safe side, composted material containing juglone should be allowed to breakdown over a period of time before use. This composted material can be used with plants that are not susceptible to juglone damage. If it is important to use it for general composting purposes, testing it first with a few tomato plants for a few weeks should reveal its level of toxicity." [Abraham]

This may also be of interest: The Walnut Tree: Allelopathic Effects and Tolerant Plants from the Virginia Cooperative Extension.

Frank Robinson's article "Under the Black Walnut Tree," Horticulture magazine, October 1986, pp. 30-33 concludes that many plants are indeed able to tolerate juglone's toxicity. Some of the juglone-tolerant plants listed in the article and in other sources are included on Viette's Beautiful Gardens website.

Season All Season
Date 2008-03-27
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Keywords: Compost

PAL Question:

What does it mean when newly purchased commercial compost smells strongly of ammonia? The compost I'm talking about is 2 yards worth and it has been delivered; I'm stuck with it. Will it improve or hurt the soil I intend to combine with it? And should plants get near it? This is serious. I have obtained all new plants and prepared everything for a new bed...but I'm not going ahead with this because of the amount we're dealing with.

View Answer:

According to Ann Lovejoy's October 16, 2003 column from the Seattle PI, a strong ammonia smell indicates "immature" compost that could harm plant roots.

Compost facilities sometimes have bad batches with too much nitrogen in the original mixture of clippings, compared to the amount of carbon, and it can be solved over time by adding "carbon-rich materials such as leaves or [finely ground] wood chips," according to a compost odor factsheet produced by Resource Recycling Systems, Incorporated. Acidity can also be a factor--less acidic mixtures sometimes remain immature until more acidic ingredients (such as leaves or needles) are added.

If you haven't already contacted the company, you might try that. At least one local company stands by its compost with a satisfaction guarantee, and that fact may encourage whoever sold you this compost to make things right for you.

Season All Season
Date 2008-05-10
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Keywords: Juncaceae (Juncus family), Carex, Soil amendments, Lawns, Compost

PAL Question:

We would like to put in a new lawn around a home where there were mostly weeds. The soil is very a heavy silt because it is river bottom land. I have access to free sand; however, I've heard conflicting advice regarding adding sand to clay -- some say yes, others no. I also have access to a large supply of free horse shavings/manure from a horse stable. Would those shavings be good to add to the soil to help lighten it and add nutrients? I don't want to go to the expense of bringing in topsoil if I don't have to. What are your suggestions.

View Answer:

Adding sand to clay soil is not recommended as a way of lightening the soil, as it "may create a concrete-like structure", according to the booklet Ecologically Sound Lawn Care for the Pacific Northwest by David K. McDonald. Linda Chalker-Scott addresses the reasons for this in depth in "The Myth of Soil Amendments Part II".

Instead of adding sand, David McDonald recommends trying to till in compost. At least two inches of compost tilled into the upper six to eight inches of soil is recommended, but four inches tilled into the upper twelve inches is preferable . Try to avoid doing this when the soil is waterlogged, as it may damage the soil structure.

Composting the horse manure and shavings you have access to could be a feasible way to obtain the compost to till into the soil. Whatcom County's WSU extension has an extensive discussion of how to compost and use horse manure.They recommend curing such compost at least a few weeks before application, and suggest that one to three months is a good, typical composting time in summer or three to six months in winter.

Alternatively, according to David McDonald, if there are a few months of warm weather between autumn and seeding time, you could simply till the fall leaves and grass clippings into your soil. Depending on your planned schedule, this could be very easy. (You can find McDonald's full booklet "Ecologically Sound Lawn Care for the Pacific Northwest: Findings from the Scientific Literature and Recommendations from Turf Professionals" online as a very large PDF.)

Another option might be to consider some sort of groundcover if you discover that establishing a lawn is an excessively extensive project. Carex species or possibly Juncus phaeocephalus phaeocephalus are more naturally adapted to heavy soils in wet areas than lawn grasses and so may be less work in the end. Though they would not be appropriate for a heavy traffic area, they would be grasslike in structure. Sagina subulata might be more amenable to heavy traffic.

Season All Season
Date 2008-05-14
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Keywords: Soil amendments, Compost

PAL Question:

I bought compost from the city of Port Angeles and in a sifted wheelbarrow of compost I got three gallons of pencil diameter "twigs". These are not composted. They break/snap and are green inside. The compost was supposed to be tilled into the garden and flower beds but somewhere in the back of my mind I sort of remember that this will take nitrogen out of the soil to compost down. Is that correct or should I not be concerned?

View Answer:

It sounds like screening your compost was a good place to start; Mike McGrath recommends removing the "odd original ingredient" from compost this way in his Book of Compost (New York, NY : Sterling Pub. Co., 2006). Woody material should definitely be removed, he says. If your compost does not seem otherwise 'off' (an ammonia smell, a sulfurous smell, very odd color), sieving off the woody material is often sufficient.

Twigs compost more slowly than other material, and you could, if you like, simply re-compost them, according to the King County Solid Waste Division.

There is some debate over the effects of inadequately decomposed material such as your woody twigs in compost and mulch. Linda Chalker-Scott addresses the question of less-than-fully composted yard waste in her May 2003 myth. She agrees that inadequately decomposed yard waste has a reputation of removing nitrogen from the soil, but writes that the way the yard waste is used affects the way it interacts with the soil. As a mulch (a layer over the soil to prevent weeds or retain moisture), it does not significantly reduce soil nitrogen, but as a compost (incorporated into the soil), it may reduce nitrogen in the soil.

If you are still concerned about the quality of your compost, Stu Campbell suggests using the following techniques on municipal compost in his Mulch It! (Pownal, Vt. : Storey Books, 2001) First, test the pH, and, if it is off, store and turn the compost for several months before using it. Mature compost should have a pH between 6 and 8, which you can test using a soil test kit or some of the other options listed on Cornell University's composting pages.

Season All Season
Date 2008-06-04
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Keywords: Oryza, Mulching, Compost

PAL Question:

Can rice straw be composted or used as mulch, or is there a risk of it sprouting? I have rice straw wattles that were used for an erosion and stormwater runoff control project which is now complete, and I'd like to use the straw in them.

View Answer:

I checked a couple of our books on grain growing, Homegrown Whole Grains by Sara Pitzer (Storey, 2009) and Small-Scale Grain Raising by Gene Logsdon (Rodale Press, 1977). Both of them refer to using rice straw as a mulch, Logsdon saying it makes an excellent mulch and Pitzer saying it can be left in the field to enrich the soil after the grain is harvested. In general, composting books don't make any distinction between different types of straw, but caution against the use of hay because it may contain more seeds.

I don't know which rice wattle product you used in your project, but some of them claim to be weed-free. You would certainly need to liberate the straw from the binding material (plastic netting or geotextile) which gives it its wattle shape before composting or mulching it. Another consideration is the source of the rice straw: if you are gardening organically, you will want to be sure that the rice was not treated with pesticides.

If you are curious about the nutrient balance in rice straw, University of California, Davis's publication, "Rice Producers' Guide to Marketing Straw," October 2010, includes discussion of this issue.

Season All Season
Date 2011-05-21
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Keywords: Weeds, Seeds, Compost

PAL Question:

When is a seed a seed? My wife and I are in agreement on not putting weeds with set seeds in the compost (and the "Easy Compost" book says just that). However, we are less sure about weed flowers (probably OK), and what about seed cases that haven't formed seeds yet? I'm thinking in particular of foxgloves right now, as the flowers are coming to an end and leaving behind the undeveloped seed cases. I'm unsure whether to compost them or not. Just an aside: our compost pile doesn't get superheated.

View Answer:

That is a very good question. I found an article in Fine Gardening magazine which discusses harvesting wildflower seeds. It is relevant because it suggests that some unripe seeds may continue to ripen even after being harvested from the plant before maturity. Whether unripe seed will eventually germinate may have to do with the permeability of the seed coat: the more permeable, the more likely the chance it will germinate.

The book Seeds by Peter Loewer (Macmillan, 1995) says that plants with tough seed coats (like legumes and morning glories) "are virtually impermeable to water and must be nicked by the gardener or soaked in warm water for twenty-four hours before they germinate. If these jackets are not broken, scratched, or eroded, water never enters and germination never begins."

I have found several references to the immature seeds of invasive plants (Ailanthus, teasel, yellow flag iris, to name a few) being capable of germination. The Complete Compost Gardening Guide by Barbara Pleasant and Deborah Martin (Storey, 2008) "weeds that show up in your garden are fair game for compost, even if they are holding seeds. [...] Weeds that have not yet begun to bloom and lack viable root buds that help them grow into new weeds can be added to any compost project, but it is important to keep weed seeds to a minimum every chance you get. [...] In every climate there are plant criminals known as noxious weeds [...] Unless you are confident and committed to processing the compost made from noxious weeds with a high-heat procedure, collect them in a black plastic garbage bag and subject them to various forms of torture before dumping them in an inhospitable place. Cook bags of them in the sun, add water and let them soak into slime, and keep track of what works and what doesn't. If your superweeds survive your torture methods and you don't have a spot in your landscape suited to use as a little landfill, discard them as garbage."

If you want to be on the safe side, avoid putting anything seedy (even green and immature) in the compost, especially if the pile is not going to get especially hot and speed the decomposition process.

Season All Season
Date 2011-07-12
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Keywords: Mulching, Fertilizers, Compost

PAL Question:

I have a large and never-fed garden. I wish to start feeding these plants. I'm composting now, but when and how often do I fertilize?

View Answer:

Has your garden been thriving in years past? If so, I don't think you need to add fertilizers. There's no single packaged fertilizer that will be universally beneficial to every plant in your garden. Different plants have different needs, and it's never wise to add fertilizer without doing a soil test.

On the other hand, you mention you are tending a compost pile. You can apply compost once or twice a year and it will be helpful to all your plants.

Here is information from The Ann Lovejoy Handbook of Northwest Gardening (Sasquatch Press, 2007):
"When do we need to feed? For ornamental plants, including trees and shrubs, spring and fall are the traditional feeding times. Spring feeds are generally fast-acting, offering rapidly growing plants the nutrients they need for a strong summer performance. A feeding mulch of compost can be fortified with fast-acting alfalfa, which will release more nitrogen if combined with composted manures. Alfalfa comes in meal or pellets. I like the big pellets used to feed goats, which are easy to spread and are available without added medication [my note: some alfalfa is treated, for use as animal feed].

"In fall, most plants stop producing fresh top growth, even though our Northwest winters are generally mild. Fall is a good time to feed roots, which continue to stretch and grow underground despite low temperatures. Adding whole fish meal to your compost feeding mulch will fortify roots with phosphorus."

Professor Sarah Reichard, director of UW Botanic Gardens, discusses fertilizers as sources of pollution in our water supply. In her book The Conscientious Gardener: Cultivating a Garden Ethic (University of California Press, 2011), she states:
"If water inevitably drains downhill, how do we stop fertilizers and pesticides from moving with it? The easiest way is not to use them. This needn't come at the cost of your plants. Most woody plants and herbaceous perennials do not require much fertilizer. Mulching with well-aged manure, compost, or other easily broken-down organic materials will supply all the necessary nutrients."

Season All Season
Date 2013-01-19
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June 24 2013 12:55:25