• If you need help identifying a pepper, disease, or plant issue, please post in Identification.

Colored Mulch - Test Results

A recent post about plastic mulch got me to doing a little thinking about the subject.

I think we all know the quick arguments for benefits for using a colored mulch: Earlier better quality fruit, Increase soil temperature, more efficient Weed Control, Decrease leaching of fertilizers, Reduce labor for cultivation around plants, etc.

The Most common types are:
•Black – Tomato, peppers, eggplant, vine crops, etc.
•Brown – Used for Higher Soil Temperatures
•Red – Early Cool Season Tomatoes
•Blue – Melons and Squash
•White – Cool Crops like Cauliflower and Broccoli.
•Silver or Metallic – Better insect control and lover soil Temp.

What I found important is that there is yield difference for what color you use.

According to GrowingTaste.Com

"Pepper - this crop appears to respond better to silver mulch (as compared to black), with an average 20% increase in marketable fruit yield and fruit size over a 3-year period. The lowest yields of marketable peppers at this location were harvested from plants grown on either white or light-blue mulch. In more southerly climates, below North Carolina, pepper response to white mulch would be entirely different. Pepper plants grown on green IRT had marketable-fruit yields similar to plants grown on black mulch."

So why does The Silver Metallic Mulch seems to be better -

“This highly reflective metallic silver mulch, made of 1.0 mil thick HDPE (high-density polyethylene plastic), disorients and repels insects such as thrips, aphids, flea beetles, and white flies by reflecting light of a particular wavelength and illuminating the normally shady underside of the leaves. With a black co-extruded bottom side, it suppresses weeds and retains moisture, but will also cool the soil from -2 to -6°F less than black plastic. Its inherent reflectivity also causes the canopy to absorb more light, resulting in up to 20% higher crop yields for particular crops, such as peppers.

In studies at the University of California Kearney Ag Center, tests show that plants grow better and more rapidly over reflective mulch than ones without any mulch. Both harvest yields and coloring of fruit increased with silver mulch. Silver mulches reflect sunlight up into the undersides of the canopy thereby increasing photosynthesis, leading to rapid growth. Mulches in general also hold temperatures at consistent levels.

In another study by the same group, aphid and whitefly numbers were lower in plants grown on reflective mulches. Reflective mulches were also shown to lower the numbers of cucumber beetles by 6 times in a study written up in Hort Technology. Apparently, insects are confused by the amount of sunlight being reflected up by silver mulch, so they are less likely to land on these plants. Silver mulch is also effective in weed control and temperature control and prevents snails from crawling across it if the shiny side is laid up.

This film is metalized one side and it is designed so the metal side (shinier side) should be face upwards. This polyethylene film is 20% stronger than other typical low-density films.”

http://www.agriculturesolutions.com/Row-Covers-and-Mulching/Metallic-Silver-Mulch-1.0mil-4-x-50.html

Here is an interesting conclusion from a study from The University Of Tennessee

Silver Mulch Produces More Peppers. Black Mulch produces Bigger Peppers.

THE USE OF DIFFERENT COLORED MULCHES FOR YIELD AND EARLINESS -University Of Conn

The Silver Metallic Mulch is slightly more expensive
As of 10-18-2011 @ Harrisseeds.com
Prices for 4’ X 600’ x 1.00 mil Black Mulch $64.95
Prices for 4’ X 600’ x 1.25 mil Silver Mulch $78.95


Most of this is cut and paste but the reference links are included for you to draw your own conclusion. For me if Silver Mulch “disorients and repels insects such as thrips, aphids, flea beetles,”, and I can Increase Yield- sign me up.

Martin
 
Great find Martin. I just don't know what I would do with 600' of it. I really would love to use it next season but everywhere I look is high quantity. I may have to suck it up and just grab a roll...
 
I hate the idea of all that plastic mixing with the soil. I wonder if you could lay down some weed barrier first then put the mulch on top of that. Or if they made a silver weed barrier type fabric I would love to try it. Either way interesting concept and definitely worth trying. I used hay successfully this year. I think it really helped to keep soil temps down on my 100+ days. To bad they did not study what yellow mulch (hay) does for the plants.

LOL After checking the link it is a roll.. mulch threw me off. I was thinking it was a shreaded plastic product. Pretty cool.
 
Great find Martin. I just don't know what I would do with 600' of it. I really would love to use it next season but everywhere I look is high quantity. I may have to suck it up and just grab a roll...

50 Ft Roll For $18.00

I think I would be better off just buying the 600 ft roll and finding someone to split it with. There are enough of us in Dallas/Ft Worth to Have a "Hot Pepper Happy Hour" and do a little trading amoung ourselves.


I hate the idea of all that plastic mixing with the soil. I wonder if you could lay down some weed barrier first then put the mulch on top of that. Or if they made a silver weed barrier type fabric I would love to try it. Either way interesting concept and definitely worth trying. I used hay successfully this year. I think it really helped to keep soil temps down on my 100+ days. To bad they did not study what yellow mulch (hay) does for the plants.

LOL After checking the link it is a roll.. mulch threw me off. I was thinking it was a shreaded plastic product. Pretty cool.

Michael- lol Yep that’s what this type of “Mulch” is - a silver colored plastic sheet used as a weed barrier. I have heard of some people using the barrier for a more than one year- Of course the thin stuff is not going to last that long. I do like the benefit of insect control - I was killed with all white flys, etal, attracted to our neighbors crape myrtles this year.
 
[ I was killed with all white flys, etal, attracted to our neighbors crape myrtles this year.

We are landscaping our yard right now... They were planning on putting several crape myrtles in the back yard. Hummm. May have to reconsider.
 
Interesting read XLNT. I used the black stuff this year and loved it. I've never heard of silver, but it sounds great for some climates.
 
Michael,

I do have them in my year, and so does my neighbor - if these ever start to "Bleed Sap", The whiteflies are attracted to the sap then they whiteflies produce their own “Honeydew” that turn dark. You can spray yours but you also have to spray your neighbors. :hell:

FYI - Hose end sprays do a damn good job spraying over the Fence. :dance: :dance: :dance: :dance: :dance: :dance: :dance: :dance:

Martin
 
So a "dumb" question.... I've used the black weed control fabric, and just put wood mulch on top for looks and to hold it down. Since you would want the metallic surface of the silver "mulch" to be exposed, how would you keep the stuff in place? I can see staking it, but a good windstorm would likely rip it up. Maybe a few strategically-placed stones?
 
So a "dumb" question.... I've used the black weed control fabric, and just put wood mulch on top for looks and to hold it down. Since you would want the metallic surface of the silver "mulch" to be exposed, how would you keep the stuff in place? I can see staking it, but a good windstorm would likely rip it up. Maybe a few strategically-placed stones?

Landscaping staples, 8 to 11"
 
Landscaping fabric works great especially in long runs with drip irrigation, the fabric breathes, its great also in landscaping usuage,
Now solid plastic, that does keep the weeds out...... pretty much blocks everything.

Only my opinion, I like to top dress around the plants base with compost and other nutes, and an occasional aeration with a hand shovel, the
the plastic would hinder any of that...

If I had the space for a large in the ground grow I'd definetely skip the plastics and weed barriers and use the "hilling method" and raised rows, maybe some weed fabric under the walk ways.

Here's a photo of one of my raised tomato beds, with weed fabric only in the walk ways with 6" of cedar chipos on top....no weeds in the foot traffic......been 4yrs. that way.


053.jpg
 
I have never heard of coloured mulches' different affects on yield, size etc. The point about illuminating the underside of the leaves makes sense. I have just filled the top of my pots with sugar cane mulch.... now I'm thinking if I should use the commercial sized roll of foil I have just sitting around on top. It seems a bit unnatural to me :think:
 
If you use foil, use the dull side. The shiny side when there are wrinkles can cause hot spots and possibly scorch the leaves. Learned this growing some "Other" plants years ago. This silver mulch sounds good.
 
I think I'm going to be adding some silver mulch over my weedblocker because the all-black weedblocker has definitely raised my soil temps a bit too much. I'm hoping it will also burn my white fly problem away :D
 
Back
Top