I like seeing post like this. Thanks.

Many of us have had the wood mulch experience.

It makes sense to me that using wood mulch full of fungal decomposers could get spores on a plant and cause a disease .

Healthy soil makes a healthy plant.

This is the right time of the year to openly honestly discuss the way to mimic natural methods of plant growth.

Linda Chalker-Scott, whom folks in Rose forum quoted so often is NOT organic. In her article attacking compost tea, she wrote how she, like the average gardener, sprays with Round-Up and uses wood-chips. I disagree, the average gardener is not dumb nor rich enough to indulge in corporate promotion.

That's promoting Monsanto, the manufacturer of Round-Up, plus promoting lumber-industry. Bayer, the German chemical company who gassed 6 million Jews in concentration camps during WWII? Bayer made a bid recently to buy Monsanto ... thank God that didn't go through. Our food prices: almonds and fruits are already expensive, thanks to the decline in bees with chemical usage.

"My definition of new organic ways is to work with one's garden & pay attention to nature, rather than blindly follow someone. "

Absolutely. Anything that is not natural can't be termed as truly "organic" in my view. We must try to find solutions that are natural and sustainable, ie, cheap. And I fear that corporate is taking over here as well. When I tell my those friends who want to go organic that you can do so many thing without wasting any money, they don't trust me. They compare what I say with the so called "organic solution" that a corporate firm will provide them in $xxx and feel that the other solution is more "professional".

Anyways, I will keep doing what I do and I am so happy to have friends like you, Sam and Jess who understand.

Now here comes my organic solution for the monsoon. I will top up all biomes with leaves, 2-3 inches above the surface of lawn.

In addition to this, I have also collected enough wood ash which I will be mixing with potash and monopotassium phosphate in the ratio of 7 : 1.5 : 1.5. I will sprinkle it in small quantities (two table spoons per biome per rain) on the surface when it rains.

Any views on this plant, Sam, Straw and Jess. Any suggestion or criticism is most welcome.

best regards

Buckwheat: A Summer Soil Boost

Recharge your soil by using buckwheat as a cover crop

http://www.rodalesorganiclife.com/garden/buckwheat-summer-soil-boost

https://www.growveg.co.za/guides/the-benefits-of-growing-buckwheat/

Phosphorus scavenger

Buckwheat solubilizes and takes up phosphorus that is otherwise unavailable to crops, then releases these nutrients to later crops as the residue breaks down. The roots of the plants produce mild acids that release nutrients from the soil. These acids also activate slow-releasing, organic fertilizers, such as rock phosphate. Buckwheat’s dense, fibrous roots cluster in the top 10 inches of soil, providing a large root surface area for nutrient uptake.

Thrives in low-fertility soils

http://articles.extension.org/pages/18572/buckwheat-for-cover-cropping-in-organic-farming

wherever I planted Buckwheat the soil is pure loam, after one season.

I found this but, I haven't been using this yet.

Plant Food
While charcoal helps to clean the soil of pollutants, it also acts as a soil conditioner. It is used as a top dressing for gardens, bowling greens and lawns. Charcoal also acts as a substitute for lime in soil additives because of the high potash content, and it can be a little cheaper than lime.

Activated charcoal adsorbs one hundred to two hundred times its own weight and comes in handy for binding, thereby deactivating some herbicides.

http://healingtools.tripod.com/char_gard.html

Jess: thank you for the info. on Buckwheat and activated charcoal. Mint likes it wet and shady, the place where I enclosed the entire bed with plastic-edging, dug down deep .. it became like a "shallow swimming pool" and mint go nuts ... grow faster than I can use.

Mint likes it alkaline. The mint where I planted in loamy & neutral soil where a tree used to be? They are not doing well as the mint next to my limestone patio (very alkaline). Fifteen years ago it took me 4 hours to kill them. I re-plant the mint today, but will put a plastic edging to stop them from invading my front walkway.

I just harvested a big bag of fresh basil and mint leaves from my garden .. will grind it with my blender to make a "green shake" for my 10 recently bought own-root roses (some are quite pale). Plus chipmunks are digging holes in my pots, so I hope that the mint & basil shake will keep chipmunks off.

Basil and mint have vitamin C (essential for plants' growth), plus vitamin A, plus Omega-3 fatty acids (the good oil in salmon), plus manganese and iron (vital for dark-green leaves). See nutritional profile of mint with 13 mg of Omega-3 oil .. I hope for that glossy-foliage like when I used alfalfa meal:

http://nutritiondata.self.com/facts/spices-and-herbs/225/2

Nutritional profile of basil is impressive, with 6% vitamin A, 2% vitamin C, 1% iron (essential for plants' growth). Plus 16% Omega-3 fatty acids. Will post before pic, and after pic, to see if leaves become dark-green and glossy:

http://nutritiondata.self.com/facts/spices-and-herbs/213/2

Khalid: Just saw your pic. of creating biome for your monsoon season. The pictures look good .. your plants are super-healthy !! With regard to what you wrote " I have also collected enough wood ash which I will be mixing with potash and monopotassium phosphate in the ratio of 7 : 1.5 : 1.5"

One cup of woodash has 1/4 cup of calcium (25%), so I would use 1/8 cup of sulfate of potash (42 salt-index) or 1/8 cup of monopotassium phosphate (a better choice, with 8.4 salt index). I already tested that in pots, 2 part calcium to 1 part sulfate of potash (NPK 0-0-50).

One-half pound of wood-ash is about 1 cup. It's salty so best diluted with organic matter like leaves. If you have banana peels with NPK 0-3-42 that would be the best source of potassium to balance out the high-calcium wood-ash. High potassium foods like potato, banana-peel, and beans also "de-salt" a medium.

http://extension.oregonstate.edu/gardening/wood-ash-can-be-useful-yard-if-used-caution

" One-half to one pound of wood ash per year is recommended for each shrub and rose bush. Spread ash evenly on the soil around perennial plants. Never leave ash in lumps or piles, because if it is concentrated in one place, excessive salt from the ash will leach into the soil."

" Generally, wood ash contains less than 10 percent potash, 1 percent phosphate and trace amounts of micro-nutrients such as iron, manganese, boron, copper and zinc. Trace amounts of heavy metals such as lead, cadmium, nickel and chromium also may be present. Wood ash does not contain nitrogen. The largest component of wood ash (about 25 percent) is calcium carbonate, a common liming material that increases soil alkalinity."

Fantastic info. about mulch:

http://grounds-ag.com/mag/grounds_maintenance_mulching_basics_covered/

" What happens with too much mulch? Over-mulching may cause stress and plant death in several ways.

Low oxygen. One of the most common causes of stress by over-mulching is oxygen starvation of plant roots. Roots must "breathe" and take in oxygen to survive (unlike leaves, which are net producers of oxygen). When oxygen levels in soil drop too low, roots decline and die, and the plant will succumb.

When wet mulch layers placed against the stem decompose, they generate heat, just as they do when composting. Temperatures may reach 120 to 140 degrees F, which is enough heat to kill young tree and shrub phloem.

The extra warmth can cause another kind of problem. In autumn, plants naturally "harden off," which prepares them for the winter cold. The extra warmth of decomposing mulch can trick a plant into delaying the hardening-off process. If trunk-flare tissue is not adequately hardened off before freezing weather arrives, the tissue may die.

Acidic mulches such as pine bark (softwood), pine needles and peat moss may have a pH of 3.5 to 4.5. When you apply them continually, they may, over several years, cause the surface soil to become too acidic.

Conversely, hardwood bark mulch may cause the surface soil to eventually become too alkaline (soil pH above 7.0),

Inorganic mulches also can affect soil pH. For example, limestone gravel used as mulch will quickly kill acid-loving plants.

Anaerobic or "sour" mulch. "Sour" mulch can occur when finely ground mulch is piled so high (usually greater than 10 feet) that inadequate air exchange occurs in the center of the pile. Without adequate oxygen, anaerobic microorganisms become active and produce several organic acids and alcohols, causing the mulch to give off pungent odors and produce extremely acidic pHs ranging from 1.9 to 4.8.

Besides black walnut, other allelopathic mulches include uncomposted sawdust of redwood (Sequoia) and cedar (Cedrus); the bark of spruce (Picea), larch (Larix) and Douglas fir (Pseudotsuga); and both the leaves and sawdust of Eucalyptus.

Artillery fungus. "Artillery" or "shotgun" fungus, caused by Sphaerobolus spp., is not so harmless. It grows on wood chips, "double-shredded" bark, leaves and dung, and occurs throughout the United States. Problems arise because the fungus can "shoot" the spore masses up to 20 feet. When they land, the spore masses resemble specks of tar and are extremely difficult to remove, leaving stains on house siding, cars and any other surfaces.

Artillery fungus has caused more than $1 million in homeowner damage claims in Pennsylvania alone. Unfortunately, many insurance companies will not cover damage claims due to "molds."

Termites. Subterranean termites live in nests or colonies in the soil and feed exclusively on wood and wood products containing cellulose. According to research by Ohio State University entomologists, termites can infest and consume wood mulches and thereby be lured closer to residential structures. However, the chances of introducing termites to a site with infested mulch are slim. This is because the reproductive queen termites needed to establish a new colony only live in the soil and are not found in the mulch.

I should emphasize, however, that you should never apply mulch so that it touches the foundation or lowest course of siding on your home, nor contact any wood surface on the home. Though it may look nice, termites can use the cover of mulch to invade homes undetected. An unmulched 6-inch buffer makes it much more difficult for termites to conceal their mud tunnels.

As a rule-of-thumb, keep mulch 3 to 6 inches away from the trunks of young trees and shrubs, and 8 to 12 inches away from the trunks of mature trees

Dr. Chris Carlson is asssociate professor and Director, Horticulture Technology, at Kent State University (Salem, Ohio)."

http://grounds-mag.com/mag/grounds_maintenance_mulching_basics_covered/

For warm climate like Australia, the below link recommends sulfate of potash, along with lime. That combo of sulfate of potash and lime is used in soy-bean crop, and farmers report that BEAT fungicides in annual yield. Lucerne hay is the same as alfalfa hay NPK 2.7-1-2.

Sulfate of potash makes sense since potassium mobility is a 3, it leaches out with rain. Also the 21% sulfur in sulfate of potash balances out the alkalinity of lime. Garden lime or dolomitic lime (with calcium and magnesium) is the best buffer for acidic rain.

http://greenharvest.com.au/GreenGardenNotes/OrganicRoseCare.html

Summer

• Fertilise repeat bloomers in mid to late summer.
• Again apply 100g of sulphate of potash per bush.

Autumn In the subtropics, hybrid tea and floribundas should be hard-pruned in February,

Winter

• In cool areas this is the main period for pruning.
• Trim bushes lightly in August, before the cold westerly winds start blowing.
• Spray with lime sulphur to kill fungal spores.
• Dust the soil with lime to provide calcium.

Here is my materials for the Cornell formula I sprayed this morning.

One gallon

Tablespoon oil

Two drops insectsidal soap

Table spoon Baking soda

.

Sam: That's a very safe & effective spray, great picture !! pH of baking soda is 8.3 to 9, very alkaline. Fungi don't like it too acidic or too alkaline.

My Lady Emma as own-root has multiflora-parentage, with 7-leaflets & tiny leaves. It's wimpy & pale in an excellent drainage plastic pot (at least 20 holes drilled !!). Then I planted in my clay, after spending 1 hour making my clay fluffy, plus digging deep down to 2.5 feet. Early summer we had tons of rain, water didn't drain fast enough, so it had very minor blackspots (5 lowest leaves).

I moved to a new hole: next to a tree, so it's drier & loamy & drains super-fast. I spent 1 hour making soil fluffy & loamy with leaves & pine-bark (multiflora likes it acidic). Leaves became dark-green & very vigorous ... new leaves are perfect.

Good drainage and solid minerals is the key to zero blackspots. Good drainage so roots don't stand in water long. I cut blooms for the vase, and if the stem is soaked in water for more than 3 days, some leaves get blackspots immediately. Solid minerals is important to neutralize acidic rain, plus to make leaves thicker & more alkaline, thus blackspots can't germinate.

My cleanest roses right now are hybrid teas: Pink Peace and Stephen Big Purple. Some pictures of 100% healthy roses, zero blackspots after their 1st flush, taken this June 27 in humid weather. My annual rainfall is 38 to 40 inch. per year. Below is Betty White rose, always healthy as own-root, pic. taken June 29:

Below are my Comte de Chambord as own-roots. I have 2 Comte as own-roots, both are 100% healthy, pic. taken June 27 after its 1st flush.

Below is hybrid tea Dee-lish, bought as a tiny own-root two months ago, now it's very tall.. zero blackspots in a plastic pots with at least 20 holes drilled for drainage.

Evelyn is always healthy in my alkaline clay, but I had to give it lime early spring when we had tons of rain to stop aphids for good. Pic. taken in hot & humid June 27, zero diseases, zero pests. Leaves are thick & glossy, fortified with minerals from alfalfa tea, topped with pea-gravels.

Below is Gene Boerner, hardy to zone 6b, but my zone is 5a, so it's a one-cane wonder after harsh winter. Always healthy, mulched with grass clippings in hot June 27, up to 90 F. Dark-green & shiny leaves from fermented alfalfa tea.

Below is Poisedon as own-root bought from Roses Unlimited May 10. In 2 months, it got huge & very healthy in a plastic pots with zillions of holes drilled for air-flow (roots need oxygen to acquire nutrients better).

Below is Just Joey, bought one-month ago as a $7 dry stick (grafted on Dr.Huey) with zero roots nor leaves. 1st blooms are ugly due to tiny young roots, but leaves are healthy. Pic. taken June 27:

Below is the base of Christopher Marlowe, 100% healthy after its 1st flush, mulched with grass clippings.

Below is my sun-sugar yellow cherry tomato .. early fruits this year thanks to fixing heavy clay with sand and gypsum. Planted this mid-May for $3 from Walmart. Pic. taken June 27:

Digging deep for drainage in clay is so important for roses' health. Digging deep is a permanent solution that helps with both blackspots and winter-hardiness, but spraying with Bayer is a temporary & harmful solution:

Khalid proved that the old ways are wrong: Plastic pots sucks, poor drainage. His roses are so healthy in "breathable" terracotta pots. There's a Texas study with Knock-out that showed it's healthier and bloom more in breathable pot like "Smart Pot".

Khalid showed proof with pics. that rooting roses in ground yield better result over pots, plus the harder-the wood, the less rot. He also showed with pics. that compost in full-sun breaks down faster, less icky molds than in partial-shade. THANK YOU.

For the past 5 years I grow over 80 own-root roses in pots first, before planting in the ground in late fall. This year is my healthiest in pots, thanks to Khalid's proof that drainage is the key to health. Plastic pots don't drain well, but I solved it by drilling at least 20 holes, see pics. below of healthy & big Poseidon less than 2 months as own-root received in the mail. The holes provide oxygen for best root-growth & fast drainage in heavy rain. Roots need oxygen to grow, plus decent calcium & phosphorus & potassium:

Pic. of recently received ten own-root roses from Roses Unlimited through the mail. I drilled at least 15 holes per pot, even on the side, for air-flow so roots grow faster. Sulfate of potash & gypsum is important for solid roots to survive zone 5a winter. Poseidon was small like the below own-roots two months ago:

New organic way is to understand each rose rather than blindly spray it with Bayer like ARS recommends.

In my alkaline clay with pH near 8, roses grafted on Dr.Huey are quite healthy ... Dr. Huey's root secret plenty of acid to release potassium from rock-hard clay.

Saw the neighbor with Angel Face (grafted on Dr. Huey), tons of blooms, and 100% healthy for many years. But multiflora-rootstock is a blackspot-fest in my alkaline clay. Multiflora-rootstock doesn't secret enough acid to un-lock potassium in my hard-mineral-clay.

Wimpy own-roots that don't secret enough acid isn't best for my heavy clay. I had a Kordes rose, Deep Purple as own-root which was 100% healthy in loamy & slightly acidic potting soil .. but broke out in blackspots when I put in my hard clay.

New organic way is to understand that each rose is different in its need for different minerals. Dave and Deb Boyd, zone 5a, noted that Double Delight and Oklahoma have a higher need for iron. True, I put red-lava-rock (high in potassium & iron) on Double Delight, and it blooms lots. But red-lava-rock was a disaster for Betty White .. its white petals turned brown at the edges.

New organic way is to understand that roses like a STABLE environment FOR HEALTH.

1) Stable moisture: After more than a week of no rain, I peeled off 2 inch. of alfalfa hay, in full sun ... the soil is soaking wet underneath, with tons of earthworm. I peeled off grass-clippings as mulch, decent moisture, but less than alfalfa hay. The driest spot is under 2 inch of wood-chips, and it was in shade !! Zero earthworms, soil is bone-dry like the wood-chips above.

2) Fluffy and loamy: I put various additives in many holes in October. Dug those holes today, June 29 .. that's after 9 months. The holes stuffed with leaves are moist and fluffy like chocolate cake. The holes stuffed with crack-corn (high magnesium) was fluffy at first, but corn's stickiness and high-magnesium glued up with my clay into concrete.

The holes stuffed with woodchips is really dry and glued up with clay like concrete. The holes stuffed with alfalfa hay is soaking wet, but gluey & compact, due to alfalfa's high-magnesium & calcium.

The holes with alkaline clay broken up with coarse sand and gypsum is very fluffy, lots of earthworm.

3) Stable pH: Clay has the best buffers (hard-minerals) to neutralize acidic rain. But loamy soil, like potting soil in my pots .. cannot buffer the acid in my fermented alfalfa-tea, nor too much acidic rain. I have to top my pots with alfalfa pellets and pea-gravel for their buffering capacity. Alfalfa at pH 5.8 is high in magnesium and calcium. Pea-gravel has pH of over 9, high in calcium & magnesium & potassium.

Re-post the info. from the other thread on why bagged cow-manure with high phosphorus &salt & antibiotics, plus nasty quick-lime used to deodorize odor, can cause SERIOUS BLACKSPOTS.

Quick-lime is a very unstable chemical, it shoots up the pH, plus binds with potassium. UP the phosphorus plus quick-lime will push down potassium (necessary for disease-prevention).

Since potassium is vital for disease-prevention, below is a chart. Also if one's soil is high in phosphorus, that will make potassium less available. Years ago I made 3 healthy roses broke out in blackspot by dumping Menards' cow manure (high in phosphorus & salt & quick lime & antibiotics).

Two years ago the Encap dry-compost granules gave my pots horrible blackspots .. too much phosphorus & salt from dried cow manure. I put some Encap dry-compost in a Thai Basil .. that broke out in blackspots !! Then I put the entire bag of Encap dry-compost in La Reine's planting hole .. it was a BS-fest, I had to move that rose to alkaline clay, and it improved.

Citrus peels is very high in potassium, banana peels have NPK of 0-3-42.

Re-post the info. that I posted in "the myth of contagious blackspots strains ..." last year in October 2015:

http://forums.gardenweb.com/discussions/3432278/the-myth-of-contagious-blackspot-strains-versus-bacteria-and-virus?n=17

The soil pH and composition does change the taste of the leaves. Early spring I bought a clump of Thai Basil at Menards. I split the clump into 2. One planted in alkaline clay soil near pH 8, and the other planted in clay mixed with acidic cracked corn (pH 4), plus cow-manure high in phosphorus ... this has many flowers, but with black-spotted & pale leaves. I tasted one leaf, it was sour & bitter, see below, pic. taken on Oct. 12, 2015:

The clump in alkaline clay (pH 8) is much taller with healthy leaves, very little flowers. The leaves are thick, sweet, and delicious. We eat that weekly. See pic below, taken on Oct. 12, 2015:

Last year I grew some tiny-rootings in pots, we had lots of rain, plus cheap potting soil that's slow to drain. But roses in pots were clean with alkaline pea-gravel, to neutralize acidic rain. Here's Perle d' Or, topped with 4 part blood meal, 2 part gypsum, and 1 part sulfate of potash, plus some pea-gravel. Pic. taken in October 2015:

Even in my alkaline clay rich in nutrients, roses consume a HUGE amount of potassium, then calcium & magnesium plus nitrogen. Bacteria can fix nitrogen, but if potassium isn't enough, or tied up, roses break out in diseases. Blooming takes tons of potassium and calcium, thus roses break out in blackspots after blooming, due to depletion of potassium & calcium.

If soil isn't loamy enough, plants can't access potassium. If drainage is poor, plants can't access potassium either. My mint in soaking wet clay never flower. Potassium is plenty in my heavy clay, but mint can't access that due to compact and poor-drainage clay.

Sulfate of potash is expensive, $10 per pound isn't enough for my many roses .. Red-lava-rock is cheaper, so I buy more cheap roses grafted on Dr. Huey, that root-stock can take hard-rock, but wimpy own-roots have to be soon-fed sulfate of potash.

When we do landscape jobs, we use pine bark mulch. We do this for 2 reasons, it is very long lasting and it is a by product of the timber industry so it ecologically sensitive ( unlike our local alternative cypress mulch which the whole tree is used for mulch and the harvesting of the cypress trees destroys our wetlands). The plants in our jobs do very well so I had never questioned the pine bark mulch. I do not use pine bark at home because it is relatively expensive. At work and at home we do not use roundup, or any spray to control disease.

We mulch for the reasons that Jess mentions;

" A mulch controls weeds, conserves water, moderates soil temperature and has a direct impact on soil microorganism activity"

Even when we are dealing with clay soils, we still have a layer of sand on the surface. We are careful to grade our beds so that water is not retained. The mulch is a dry layer. I think that because it is never saturated, even in periods of heavy rainfall, keeps it from drastically effecting the ph of the soil. Pine bark in potting soil does effect soil ph and I am theorizing that it is because it remain wet. Our potting soil comes "ph balanced".

I am just making guesses on why pine bark work here and it such a disaster further north.

Our challenge, in the deep humid south, is to try to get organic material in the soil, and not having it all burned out by the end of the summer. At home, this spring, I applied 4" of wood mulch supplied for free by companies that prune along power lines for the utility companies. I now have less than 1" remaining on my beds. If I use too much mulch, I end up with severe nitrogen deficiency.

I have just receive a 25 yard load of partially composted peanut hulls which I will add to my beds in the next few weeks. I am hoping that is will be a good replacement for my free wood mulch. If it works well in my gardens, then we might try it as a replacement for pine bark at work.

Val: Thank you for sharing your experience in sandy & hot Florida.

In my garden of heavy alkaline clay, what's on top gradually change what's below to become like what's on top. Clay holds water well, but the soil below DRY WOOD CHIPS become dry like the wood-chips above it, even in shade, if there's no rain.

The soil below leaves become wet & fluffy like the leaves above it. Leaves and alfalfa hay holds more water than dry wood-chips.

I flipped up the 2 inch. layer of leaves mulching heavy clay in FULL-SUN, and it was soaking wet, plus tons of earthworms after 2 weeks of no-rain. Alfalfa hay locks in moisture even better, after 2 weeks of no-rain in full-sun .. it's soaking wet clay below, plus earthworms. Leaves has some nutrients, and alfalfa hay has NPK of 3-1-2, good nitrogen & decent potassium. I would choose alfalfa hay as the top choice for mulch.

Found a study "Effect of Peanut Hull and Pine Chip Biochar on Soil Nutrients, Corn Nutrient Status, and Yield"

http://naldc.nal.usda.gov/download/41358/PDF

"Nitrogen in the peanut hull biochar (209 kg ha–1 at 11 Mg ha–1 rate) was not available during the study based on corn tissue concentrations. The peanut hull biochar linearly increased Mehlich I K, Ca, and Mg in the surface soil (0–15 cm). Th e

increased available K was refl ected in the plant tissue analysis at corn stage R1 in 2006, but not in 2007. Pine chip biochar decreased soil pH, but had no effect on other nutrients."

**** From Straw: Biochar is slow-burning fresh stuff under soil (with very little oxygen) .. it's like a fast-decomposition. So the peanut hull gives zero nitrogen, but increase potassium, calcium, and magnesium. Pine chip decreased soil pH, and have zero nutrients. Surprising grain yield DECREASED with both applications. I think the shortage of nitrogen is the major factor for decrease in grain yield.

Valrose and Straw: I used pine bark in my pots and rose beds last year and didn't have good results. In pots, it lowered the soil pH, making it acidic that encouraged fungus. In beds, it encouraged termite. This year, I have been using dry leaves and grass clipping all the time and the results are much better. I use grass clippings in rose beds only.

best regards

Straw, thank you for the link on peanut hulls. I have had trouble founding out any info on them. The thing that I am most concerned with it is peanut allergies even though I am using a partial composted product.

I see that the soil dries out under wood chips, I use wood chips at home because they are free. I am guessing that is because the wood chips wick the water out of the soil and it is evaporated into the air. As the wood chips decay this is no longer a problem. ( We have a similar problem with plants that were grown in a Canadian peat and perlite soil mix. When they are planted, the root ball dries out very fast. We have to water 2x a day until the roots have grown into the surrounding soil. This might not be a problem where you are, I think it has to do with the different water holding capacities of the potting soil vs sand. The sand wicks the water away. )

When I use old hay, I have experienced the same as you describe with leaves and grass clippings. Maybe I should look for old hay to mulch my beds.

The pine bark mulch that we get here is stripped off the pine trees leaving almost no wood attached. Pine bark mulch functions as a weed deterrent and slows down evaporation. Pine bark will be dry on top but the soil underneath is moist. It decomposes very slowly and is not suppose to harbor termites. My biggest concern is that it does not add organic material to the soil.

Some clients insist that we use rock mulch. The landscapes with rock mulch are much harder to maintain. They require more fertilizer and suffer nutritional deficiencies.