Harlequins Gardens

Boulder's specialist in well-adapted plants

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Home | Blog | Plant and Soil Health / Disease

Plant and Soil Health / Disease

Watering in July

We generally agree that the term “Xeriscape” (water–conserving landscape) applies to plantings watered deeply one a week. However, in July it’s safer to water twice a week. At Harlequin’s Gardens, some of our shrubs and trees are only watered once a month, and twice in July. One of our gardens of mostly native shrubs and trees is never watered. 

What does that mean, “water deeply“? It means that when you irrigate by hand or sprinkler or drip, the soil should be moist to a depth of at least 4″. Moisture meters and the old ‘screwdriver test‘ are not as accurate as digging a small hole 4 to 6” deep and feeling the soil. If it is dry at 4″ just after watering, you will need to water longer. 

You can water less frequently if:

1-You have added compost to your soil 

2-You have added expanded shale (10-20% by volume) to your soil 

3-You have inoculated your plant roots (especially at planting time) with beneficial mycorrhizal fungi 4- you have covered your soil with mulch, or if your plants cover and shade the soil. 

Do not:

1-Water lightly every day (except if temperatures exceed 95 degrees); it encourages shallow rooting and evaporates rapidly. 

2-Water deeply more than twice a week, creating saturated soil that excludes air (plants and beneficial soil life need air as much as they need water). 

3-Plant too close together, creating competition for water. It’s better to mulch the gaps between plants while you wait for them to fill in. 

4-Mix plants with high and low water needs in the same planting bed. 

When you plant in July:

1-Prepare the soil well, incorporating 30% compost (a 1-2” layer spread on top and then dug in to a depth of 6“) 

2-Inoculate the roots of the new plants with mycorrhizae, which will vastly improve transplanting success of most species 

3-Treat your new ‘babies‘ as if you’d just brought them home from the hospital, i.e. water them frequently, shield them from hot sun with shade cloth or another source of shade until you see new growth. Then you will know that their roots have reached into the surrounding soil. 

4-Place a ‘flag‘ next to every new plant so you can quickly see which plants need the most attention. 5- If your soil is very dense clay (a 10“-deep hole holds water for 30 minutes or longer, add expanded shale (10-20% by volume) along with compost. 

6-If you’re leaving town, even for just a few days, give your special watering jobs to someone you would trust with your life. 

How to Plant in the Heat

It’s not ideal, but sometimes you have to plant in the middle of a heatwave. Fortunately, it can be done successfully, even here in the high, windy and dry zone. High temperatures, wind and strong sunlight cause water to evaporate from plant leaves faster than the roots can take up water.

The key to survival of new plantings is shade – for the plant and for the soil.  Here are some tips:[Read More]

Compost Tea and a New Organic Compost!

Our compost tea will be ready this week, hopefully by Friday. Our tea has always been good, but this year we are working on making it even better. Please let us know if you can see good results from using it, and if it seems to be more effective.

Say Hello to ECOPLUS Organic Compost! We are replacing our A-1 Eco-Grow compost with the newly-available ECOPLUS Organic Compost, an OMRI certified organic compost made by A-1 Organics in Colorado.[Read More]

News Flash?

This morning’s broadcast of This Week In Water on community radio station KGNU announced that results of a 5-year study conducted by the U. of Washington found that using regenerative farming practices such as not tilling the soil, growing cover crops, and having plant diversity affect the nutritional content of vegetables.  

[Read More]

Very Special Products to benefit Your Soil Life and Your Plant Life

It all starts with the Soil, and we have some very special products to benefit your Soil Life and Your Plant Life!

All of these are sold pre-packaged, and we bag many of them ourselves in refundable, reusable plastic bags. Our Compost Tea is sold in refundable, reusable 1-gallon jugs, or you can bring your own.[Read More]

Suggestions for Remediating Singed and Burned Gardens

(Durango Before and After Fire. Photo Credit: Colorado State Forest Service.)

After the Fire

We are so grateful that nearly all the folks in the Marshall Fire burn area were able to evacuate quickly and safely. The horror of all the lost homes and their contents, the pets trapped, and the gardens obliterated is outweighed by the survival of all but two residents.

[Read More]

Snow and Soil!

Wow!  That was an impressive snowstorm, even if it did arrive several days later than predicted. We know how hard many of us have had to work to clear paths through it.  And we hope everyone stayed safe, warm, healthy, and well-fed throughout. Colorado has been experiencing a long-term regional drought, so this addition to our mountain snowpack couldn’t be more welcome. Just think what a difference all this snow can make for Colorado’s farmers, many of whom have seen their ditch water allotments disappear in early July for the past several years.

[Read More]

Feeding our Soil while Carbon Farming

Photo Credit: Aaron Favila – AP, and The Daily Camera.

Harlequin’s Gardens has become a member of the recently formed Coalition for Local Compost Climate Action. This is because Boulder County is getting ready to build a local composting facility to turn our organic wastes into fertility and climate action, which is very exciting!

For years we have been talking about the need for a local public composting facility. And now, driven by the pressure of Climate Change, it is even more obvious. We need to apply Nature’s waste recycling system, using microbes to remove valuable organic matter from the waste stream and turn it into healthy soil.[Read More]

It’s Time to Feed Your Plants

This is the perfect time to feed your roses, perennials, and lawn using a slow release organic fertilizer. This type of fertilizer won’t push undue growth now, but instead help your plants prepare for next spring. We recommend Mile High Rose Feed for your roses, Alpha One Fertilizer for your perennials, and Nature’s Cycle Organic Lawn Fertilizer for your turf.

[Read More]

Shrub and Tree Recovery Fertilizers and Mineral Supplements

AGE OLD ORGANICS DRY BLENDS

Grow Formula: 8-4-1.  a naturally based, high nitrogen blend of nutrients, including 1% calcium, which are slowly converted by soil microbes into plant available forms. Grow Formula is an excellent nutrient addition to potting mixes or soils and can be used as a top dressing on existing gardens and lawns.

[Read More]

BUILDING TOPSOIL AND SOIL FERTILITY by Mikl Brawner

“Where can I get some good topsoil?” That’s a question I hear frequently at our nursery. And I often look wistfully towards the plains and say, only half-jokingly, “You can get good topsoil about 800 miles east of here.” That’s where I grew up, in Iowa, and where two tomato plants feed a family of six. It’s not that local suppliers are trying to deceive us when they sell Colorado clay as topsoil; it’s just that the glaciers didn’t dump three feet of loam on top of our clay.[Read More]

Insectary Plants: Let Nature Manage the Pests

It’s a common idea that Nature, left to its own devices, comes to some kind of balance. If one organism gets too numerous, something else will increase to reduce that population. In the case of monocultures created by humans, there is an enforced imbalance that has to be propped up with lots of energy and effort. So in the pursuit of sustainability, humans are opening our eyes to the possibility of biomimicry, imitating Nature. We are coming to the realization that biodiversity is far healthier and less energy intensive than monocultures born out of the aggressive hubris to control Nature. “Let Nature take her course.” But we can stack the deck in human favor first.[Read More]

Non-Toxic Weed and Pest Control

Non-toxic Herbicides

Summer is a successful time to kill weeds, either by mechanical weeding or with herbicides. But toxic herbicides, like Roundup are not solutions we recommend. Roundup in particular was once believed to be quite safe, but now is shown to be harmful to soil life including nitrogen-fixing bacteria, amphibians and is a probable human carcinogen. Roundup formulations can be up to 400 times more toxic than the active ingredient, glyphosate.

At Harlequin’s Gardens, we only sell non-toxic products, but not all non-toxic products are actually effective. Four years ago we tested five non-toxic herbicides and found only two to be really effective: 20% Vinegar and Avenger.

20% Vinegar is 20% acetic acid. It is a non-selective organic acid that quickly kills many weeds, then quickly biodegrades. Repeated use can acidify the soil which is usually a benefit in our alkaline soil. Be careful not to spray desirable plants, and be careful to protect your eyes, especially on windy days. It is most effective on small plants. Repeated applications may be necessary on perennial weeds.

Avenger is a citrus oil weed killer that we found to be equally effective as the vinegar. It is certified organic and is biodegradable. Avenger is non-selective so care must be taken to keep spray off desirable plants. It comes in a ready-to-use (RTU) formula and in a concentrate which may be mixed stronger for tougher, perennial weeds. Like vinegar, it is most effective on small plants, and is best sprayed during hot weather in direct sunlight.

In order to “control” bindweed and other weeds with extensive root systems, don’t let new growth get longer than 2″ or the weed will revive.

 

BLISTER BEETLE: We have been hearing reports of Blister Beetle attacking clematis. This is a light grey, long beetle that can defoliate a clematis vine in 2 or 3 days. We have found that an organic product called Veggie Pharm actually kills this beetle. It must be sprayed directly on the beetle. (Don’t try to pick up a Blister Beetle; they can raise a blister)

 

Tree Wrap: We recently saw a big buck with his antlers in the velvet stage. This the time of year deer cause the most damage, when bucks rub their itchy antlers on smooth, usually young tree trunk, tearing the bark. Sometimes a young tree can be girdled in one night. We carry a very good spiral plastic tree wrap that protects trees from deer, rabbits, sun scald in winter. It is superior to paper wraps because it lets air circulate so moisture does not decay the bark. It can be left on in the summer and it expands as the tree grows. Once the bark is older and tougher, it will no longer need protection.

How Do We Manage Fireblight

Colorado is said to be the worst state in the US for fireblight, and 2018 was considered by many to be one of the worst years in Colorado. Fireblight is a serious disease affecting apples, crabapples, pears, Mountain Ash and hawthorn, and sometimes quince and pyracantha (supposedly up to 73 species of plants).[Read More]

Small Trees for Eastern or Northern Exposures

Shade trees 40’-60’ high and wide are great on the south and west sides of our houses and offices. They reduce temperatures and reduce cooling costs in the warm months, but they are not always appropriate. We don’t want dense shade where we grow most xeriscapes, rock gardens, herb gardens, most natives and many perennials. In addition, there is no need for big shade trees on the north side, and the morning sun is usually welcome on the east side of our houses and workplaces. And many plants prosper in morning sun and afternoon shade. It is also significant that a 20’ tree costs far less to have pruned than a 40’ tree. So it seems to me we should be growing small trees under 30’ tall on the east and north sides of our buildings.[Read More]

Stressed Trees: How to prune and care for them

Trees have it hard in Colorado. If it’s not the shallow and lean topsoil, it’s the low rainfall and low humidity, or it’s the heavy wet late spring or early fall snows, or like last November, it’s the dramatic temperature changes. After a warm and beautiful fall without a killing frost until November 11, we experienced a 77 degree drop in temperature between November 10 and November 12. This was one of the three largest temperature drops ever recorded in the Denver area, the other two were in December 2013 and January 2014.[Read More]

Biological Thinking

It has been suggested that this period of the 21st Century might well be called The Age of Biology, because the biggest challenges will be biological and the biggest breakthroughs will be in the realm of biology.

In this article, we will continue the discussion from the last issue on Biological Agriculture and Gardening, but this time going into specifics of biological thinking, biological discoveries and applications that improve plant and food success with biological solutions.[Read More]

Food Safety and GMOs

Food safety is one of the most critical issues of our time. What we eat is directly related to our health, and health care has a direct impact on our personal and national economies. Major chemical companies like Monsanto, Bayer, Dow and Dupont have introduced 86,000 synthetic chemicals into our environment, food, drugs, cosmetics etc and most of them have never been tested for toxic effects on human health and the environment. Since the mid 1990s, some of these same companies have been filling our grocery stores and feed stores with genetically engineered food products which may be causing serious health problems but are being approved by our government without safety testing.[Read More]

Invasive Plants and Weed Profiles

Last month we raised the issue of invasive introduced plants and the idea of being responsible gardeners who respect our native habitat and make an effort to not release invasive plants into the wild. We began with obvious noxious weeds that are having strong negative impacts on our native populations of plants and animals. This month again I am profiling weeds which have been declared as noxious, but this time a question is beginning to arise about under what circumstances are some of the less aggressive weeds invasive? In other words, is it possible that we might find a middle way that guides us strictly with the truly harmful invasives and more leniently with the less aggressive and more useful weedy plants? These are questions I am asking myself and will be asking in future interviews. We also welcome your views on this issue.[Read More]

Invasives August Issue

In February 2000 President Clinton established the National Invasive Species Council. Agriculture secretary Dan Glickman, Commerce Secretary William Daley and Interior Secretary Bruce Babbitt were asked to work together on a plan to minimize the economic, ecological and human health impact of invasive plants and animals not native to the US. The executive order on Invasive Species directs federal agencies to prevent the introduction of invasive species, to control populations of such species in a cost-effective and environmentally sound manner, to monitor populations, restore native species, conduct research and promote public education on invasive species.[Read More]

Invasives Intro

One of the hot subjects in horticulture these days is the issue of the invasiveness of introduced plants. Since they did not evolve here, they lack natural enemies, and whereas most are harmless, some have engulfed vast areas of wilderness, national forests, range and farm lands. This has led some people to campaign for “natives only” and others to attack the introduction of new plants as an ecological nightmare. In response to these attacks some in the plant industry have dismissed these fears as invalid over-reactions. As Colorado gardeners, most of us can be both excited by new plant introductions that are well-adapted to Colorado conditions, and feel very protective of our natural ecosystem and our native plants. In a series of articles, we hope to uncover some truths regarding these issues and to educate ourselves about how to work with this situation in a constructive manner.[Read More]

Feed the Soil, Not the Plant

It is widely known that nitrogen is essential for plants. It is a major component of amino acids, DNA and chlorophyll. It is necessary for photosynthesis, the alchemical process of turning sunlight, carbon dioxide, minerals and water into oxygen and sugars that is the food that feeds life on earth. In Colorado, most of our soils are deficient in nitrogen.

But too much nitrogen can be a problem, especially high nitrogen chemical fertilizers. Bill McKibben, author of The Art of Balancing Soil Nutrients states, “Although all plant nutrients are critical, none seem to produce such quick and dramatic effect on plant growth as nitrogen does. It is because of this reason that nitrogen has been over-used and abused.” A 20%-30% nitrogen fertilizer can make a spring lawn turn bright green practically overnight, and can make plants in a greenhouse or garden grow and look mature really fast. So what’s the problem?[Read More]

Flood Recovery for the Garden

Flood recovery is not a problem most of us have had to deal with before so we can only try to solve the problems individually and make adjustments in the future.

The main problems seem to be:

1) Soil washed away-erosion

2) Soil dumped on top of plants, trees and existing soil

3) Plants washed away

4) Weed seeds deposited on the soil 5) manure and sewage and unknown contaminants deposited on the land[Read More]

Mulching the Garden

MULCHING THE GARDEN

Benefits of Mulching:

1) prevents evaporation; holds moisture

2) reduces weeding; makes weeding easier

3) reduces fungal diseases; prevents splashing of spores onto bottom leaves

4) feeds the soil; as mulch decomposes, worms take nutrients into the soil[Read More]

Mulches and Mulching

 Applying a mulch around our plants can be one of the most effective ways to improve their health and success, especially during hot and dry conditions like we had in 2012. Mulches have many benefits, but it is important to know how to use them to avoid problems.

 Mulch conserves water by reducing evaporation 10%-50%. Usually a 2”-4” deep layer is best, and the material needs to be open enough to admit rain and irrigation and dense enough to resist evaporation. It is a good idea to apply mulch after the soil has been deeply watered or soaked with a good rain. Then the mulch will hold the moisture. Beware of materials like unshredded leaves which can act like shingles, and dry compost or sawdust which are hydrophobic, meaning they are difficult to wet. These problems are worse on a slope where water can run off instead of penetrating.[Read More]

Nitrogen Fixation and How We Can Use It

Nitrogen is an essential nutrient for all living things. Where does that nitrogen come from? It comes from the atmosphere, which is composed of 78% nitrogen; but that gas is quite inert, meaning it can’t combine with other elements until it is broken into a simpler form. This process takes a lot of energy to “fix” the nitrogen. There are three processes that can fix nitrogen: atmospheric, Haber Process and biological.

Atmospheric fixation occurs when the high temperature of lightning splits the nitrogen gas so it bonds with oxygen and moisture in the air to form nitrates that fall to the earth with rain. This natural fertilization benefits plants. Some people have asked, Is it my imagination that my grass looks greener after a thunderstorm? Maybe not; it could be due to the nitrogen as much as to the water.[Read More]

A Bad Year for Fire Blight

This is a bad year for fireblight which is a bacterial disease which affects mostly apple, pear, crabapple, hawthorn and Mt. Ash. It is spread in the presence of moisture and enters the trees through wounds and open blossoms. Colorado is the worst state in the US for fireblight.

Because of our moist spring and extra wounding caused by hail, there is a lot of infection. Symptoms include black, hooked twig ends, brown or blackened leaves, dried up fruits and sunken cankers that can be a dull orange or black. Fireblight is a difficult disease to manage because there is no cure. Spraying chemicals is not recommended by CSU because they are not very effective, timing is critical and spraying must be repeated.[Read More]

Fireblight: How to recognize it and deal with it (1997)

One of the most damaging and most perplexing diseases of the Front Range is fireblight. It is a bacterial disease affecting apples, crabapples, pears, Mt. Ashes, pyracanthas, quinces, hawthorns and occasionally cotoneasters. Fireblight does not affect cherries, plums, peaches or shade trees.

When the bacterium with the lovely name Erwinia amylovora enters the trees through an opening such as a wound, a pruning cut, the open blossom or leaf pores, the tissues quickly die causing blossoms and leaves and young twigs to suddenly wilt and turn black as if scorched by fire (hence the name “fireblight”). As the bacteria spread through the tissues, secondary infection continues through the season and bark areas die, become sunken and turn black or reddish-orange. These areas are called “cankers”. Sometimes large numbers of leaves turn black but the infection stays confined to small twigs; sometimes entire large branches die; occasionally the entire tree will die.[Read More]

Japanese Beetle is Here

Japanese Beetle is one of the most damaging insect pests in the Eastern and Midwestern US, but until recently, Coloradans were spared that challenge. It entered the US in 1916, but took until 2003 before a population was established in Colorado. This first infestation was in the Palisade area on the Western Slope. Even though eradication efforts were mostly successful there, established populations have been found since 2005 in Pueblo, southern Denver, Englewood, at DU and at Denver Botanic Gardens. Populations are being seen now in Boulder and Jefferson County.[Read More]

Managing Weeds Organically

 

This is the perfect time to apply Corn Gluten to prevent new weeds.

There are simple steps you can take now to keep your garden organically weed-free all season long 

[Read More]

Pyrethrum Insecticides: Are they Safe?

Pyrethrum is one of the best known botanical insecticides, effective against a wide variety of insect pests and generally considered safe to use. Is it really safe? To answer any question about pyrethrum it must first be explained that what is referred to as “pyrethrum” can be many different products. There is pyrethrum, the raw flowers; pyrethrins,the extracts from the flowers; and pyrethroids, synthetic pyrethrum. In addition many other insecticides and enhancers are often added to formulations which are called “pyrethrum”.[Read More]