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Bottom-watering seedling trays with cotton flannel prevents water-logging
Posted on Nov 15, 2013 1:09 PM

You can bottom-water seedlings right in their tray if you put a  a fuzzy capillary mat between the pots and the water-holding tray under them.  Add only a little water at a time, and the mat will carry that water equally to every pot or cell.

  Cotton Flannel Bottom Watering 

A capillary mat cures over-watering and prevents water-retentive mixes from drowning seedling roots.
It also makes bottom watering <u>easier</u> than top-watering, and more uniform!

If you find it messy or time-consuming to bottom-water small pots, seedling flats, insert cells or propagation trays, cover the bottom of their solid 1020 tray with cotton flannel or a commercial capillary mat that is absorbent on both sides.

Then add only small amounts of water onto the mat, so that the mat is very wet but no standing water is visible.  The mat and the grooves in the tray do hold a small reserve of water that each pot pulls from when it needs water.

Thumb of 2013-10-18/RickCorey/67790f     Thumb of 2013-10-18/RickCorey/a82515
This capillary watering mat spreads the water evenly to all the plants. Every cell and pot gets an equal opportunity to sip only what it needs.

If you top-water and flood some pots but miss others, the mat will actively pull water down out of the water-logged pots and transfer that excess water to the drier pots.  Capillary action plus gravity maintain similar moisture levels in the bottom of every pot and in the mat.  

Remove standing water from above the mat with a turkey baster, unless you'll be gone for a week.  Figure that the mat and the bottom layer of potting mix are approximately equally soggy or dry, when you consider adding or removing water from the tray.

If you use propagation trays or "six-pack" inserts, make sure their bottoms rest on the mats to establish a capillary connection to the soil.  

Thumb of 2013-10-18/RickCorey/42dd42    Thumb of 2013-10-18/RickCorey/6c9a92

You may have to trim the edges or rims off the propagation tray so it doesn't rest on the sides of the 1020 tray instead of on the bottom.

<-  Bad, the insert rims hold the cells UP, off  the mat.                                                                      Good - the insert rim fits inside the 1020 tray ->

 Thumb of 2013-10-18/RickCorey/89cec3     Thumb of 2013-10-18/RickCorey/ee4237

Note that the mat does not quite reach the edge of the 1020 tray in the last photo above, and some other photos. That is OK as long as the holes in the bottom of the cells or pots are over the mat (as you can see through the bottoms of the 6-pack cells in the last photo above.

If you use several small pieces of fabric to cover the tray, I suggest slight overlaps or bridging wicks so that every piece of matting shares water with every other piece. That way, every plant in the whole tray has water as long as any plant has water.  And no cell will have any perched water drowning roots while any cell has less than capillary saturation.

I like to assure that the mat can suck every drop out of the grooves in the 1020 tray. To do that, I cut a few strips of cotton flannel or other thick wicking material that will fit down into the drainage grooves. They set up a capillary path from the bottom of a few grooves up to the flannel, so it can always drink the tray dry.  

If you use this 'flannel method' to bottom-water large potted plants with soluble fertilizer for months, the pots might accumulate salts or unbalanced nutrients (like any bottom-watering method).  To cure that, top-water heavily every few months until a good bit of water comes out the bottom of the pots.  Remove that salty water with a turkey baster or wet-dry vacuum.  Suck the water out of the tray grooves as well, to give the mat more capillary "pull down".  That will flush away excess fertilizer.

Thumb of 2013-10-18/RickCorey/5ebdc8
I haven't adapted this method to have a deep reservoir, but I think it could be done by draping the mat over some elevated platform or grid and dangling one or both long edges into the 1020 tray, and filling that tray pretty deep before leaving.  Or maybe by setting a gallon jug of water 6" above the mat, and trailing a few lengths of cotton twine, parachute cord or other wick from the bottle down to the mat.  But test it first to be sure it won't overflow in a few days!

- - -  Prevents Perched Water Layers - - -

Since the pots are never submerged at all, the bottom half inch of the pot never floods, and a "perched water layer" never forms.  The flannel mat's capillary "pull down" power is increased by gravity when the mat is not soaked.  This draws fresh air down into the bottom of each cell, so it stays aerobic, sweet, and receptive to roots.  

Without a mat, an over-watered shallow cell with only baby roots might  <u>never</u> drink all the excess water from a perched water layer.  With little or no air circulation, the soil mix in the bottom stagnates and becomes anaerobic or hypoxic.  Roots are stunted, or drown and rot, or just never penetrate the bottom half of the shallow cell.  Fermenting or anaerobic microbes may take over.  That's even worse for roots.

The situation is even worse if the soil mix is peaty and fine and holds too much water.  The only air spaces in the soil are narrow.  Even a very thin film of perched water will exclude <u>all</u> air from a mix with too much peat and not enough coarse fiber!  In that case, the entire pot or cell may become a perched water layer (no air spaces).    

A capillary mat lets a peaty mix recover from over-watering much faster, if you remove standing water from the tray and grooves.  

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"OP Variety" vs. "Hybrid Variety" vs. "Openly Pollinated"
Posted on Apr 26, 2013 6:54 PM


"OP Variety" vs. "Hybrid Variety" vs.  "Openly Pollinated"


1.  "OP variety"

An OP variety is genetically stable enough that it "comes true" to it's parents if it pollinates itself.  That stability was achieved by inbreeding a strain for several generations while selecting for the desirable traits, and "rouging out" any plant that lacks the desired traits.

All heirlooms are OP varieties. 

Once it is stabilized, you you can maintain and conserve an OP variety by allowing it to pollinate itself via wind and insects  - as long as other varieties of the same species are not close enough to cross-pollinate. 

Even if "isolation distances" are not observed, you can multiply OP seeds "mostly pure" by surrounding a patch of that variety with plants of different species.  It also helps to mostly save seed from plants in the center of the patch. 

A bee CAN travel ⅓ of a mile between visits to its hive.  But it's very rare that a bee will visit a plant 1,500 feet from your yard, and then fly directly to YOUR plant and cross pollinate it.  So unless you need 99% genetic purity, avoiding the same species in the same bed, and then not worrying about cross-pollination works quite well.  Next year, just pluck any plant that does pop up lacking the desirable traits (before it can pollinate its neighbors). 

 2.  Hybrid Variety

The opposite of an OP variety is an F1 hybrid variety.  Those require human intervention to produce OR maintain.  Usually there are two or more inbred "parent" varieties that were developed and maintained the same way any OP variety is created and maintained. 

The named F1 cultivar is produced by carefully preventing the seed parent from pollinating herself, while someone transfers pollen from the male parent.  It's complex and artificial, like plucking anthers and stamens, bagging seed blooms, collecting pollen, and manually pollinating a stigma with a small brush or Q-Tip. 


3. "Openly Pollinated"

The opposite of complex and artificial pollination through human intervention is allowing plants to pollinate themselves and each other via wind and insects.  If you allow F1 hybrids to do that to themselves, you get a blurry mix of 'blah' plants without the special traits the F1 cultivar was appreciated for.

If you let an OP strain do that to itself, you propagate the desirable OP strain and conserve all its desirable and familiar traits.

Say you let an OP variety pollinate itself openly, and label the seed pkt "OP". You haven't said whether you prevented, allowed, or encouraged cross-pollination with other varieties.  If the recipient thinks you meant " here's seed from that OP variety we like so much", he might assume you intended it to be less than 20% cross-pollinated.  After all, that IS how OP strains are propagated: openly pollinated BUT with at least some attention paid to isolation.

But if the recipient thinks you meant "here is seed that was freely and openly pollinated by wind and bees", he might think that you're hinting that it was pollinated by lots of who-knows-what, and hence is likely to grow out an interesting mix of surprising, varied and unique colors and shapes.  He might hope the sender meant "openly pollinated AND heavily cross-pollinated by surprise neighbors".   


But "openly pollinated" doesn't really specify EITHER paying attention to isolation OR encouraging interesting cross-pollination.  It doesn't mean "selfed", and it doesn't mean "out-crossed" either.  All it really means is "I didn't bag these blooms and play around with Q-Tips." 


However, I think that less than 0.1% of hobbyist seed traders collect their trade seeds by bagging-and-dabbing.  And the few that do go to all that trouble would mention it and name the parent strains.


My suggestion is that using "OP" on a traded seed packet to mean "openly pollinated" actually conveys no new information at all. 


Instead it confuses people who think that "OP" means the same thing as it does on commercial seed packets: a stable variety that "comes true" to its parents. 


I wish that the common usage was something different, like

"PB" for pollinated in a bag or with big isolation distances

"PI" for pollinated in some isolation,

"PP" for promiscuous pollination.  

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Plug Trays, Inserts and 1020 Trays
Posted on Apr 5, 2013 3:21 PM


"1020" only means the size of the tray. A 1020 tray can have a plain bottom, or slits for drainage, or an open, web bottom.  They are (usually?) undivided and used for carrying pots, inserts or "liners" (small, square pots).

Thumb of 2013-04-05/RickCorey/f18be3

"Web" refers to very open  bottoms.  Mainly they hold pots so you can carry them around easier, and so you can dunk them into something bigger for bottom-watering.The webs are so far apart that sometimes I lay down a piece of window screening so that small pots will be better supported and less likely to tip over.

I think web trays tend to be sturdier than the kind shown above:

Thumb of 2013-04-05/RickCorey/a4d8d8

 I thought all 1020 trays were 11"x22", but now I see they are not really quite that long, and different manufactures make slightly different lengths:
11" wide x  21.37" long  x 2.44" deep
11" wide x  21.25" long  x 2.44" deep

Besides being slightly variable in length, the "standard" defines the outside dimensions, not the inside dimensions.  That must really drive commercial greenhouse owners crazy, when they buy a case of 100 insert trays or plug trays (propagation trays) that don 't quite fit their 1020 trays!  To be sure that inserts and plug trays really will fit 1020 trays, you might have to buy both from the same supplier. The depth of a tray matter if you want your inserts t6o sit flat onj the bottom without you having to trim off the inserts' lips.

An "insert tray" is always very flimsy, 11"x21", and usually lets you tear them apart in 'paks' of 4 or 6.  That's where the term "6-pak" comes from, if you never drink beer. They can be like a "tray of shallow, flimsy pots taped together so that they don't tip over", if there are only 12, 16 or 24 cells.  If there are 64 or 72 cells, each cell will be only 1-2" square, so small that they only hold seedlings briefly, until you can get them into the garden.  

The whole 11"x21" sheet of inserts is so flimsy that you really NEED a 1020 tray under them, or they fall apart when you try to lift them.

These are deep  "1206" inserts: 12 6-paks.   (I call these 72-cell inserts.  They fit a 1020 tray with 12 rows of 6 cells per row.)

Thumb of 2013-04-05/RickCorey/43f008

more photos of "deep" inserts:

diagrams  of inserts with names:

What are plug trays (propagation trays)?  Sturdier than inserts and not tear-apart-able.  They are sturdy enough that, if you don't mind mud on your shelves, they don't need a 1020 tray under them when  you move them (just keep one hand underneath, as with a baby).

The cool thin g about plug trays is that they are aimed at commercial growers and super-gardeners who want to propagate vast tracts of seedlings.  Like 128, 200, 288, 392 or even 512 seedlings per tray!  Cells in the 512-tray are only 0.56" square!  

They have rows and columns of cells like 8x16, 12x24 and 16x32

tiny plug trays

Thumb of 2013-04-05/RickCorey/801223

And here is a tray that has 20 rows instead of hundreds of cells:

Thumb of 2013-04-05/RickCorey/161697

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Many Weather and Climate Related Web Sites
Posted on Mar 18, 2013 7:34 PM


Links related to weather:  Forecasts,  History Archives,  and Neat Features

~ Degree Day Calculator by Zip Code  

~ Weather Underground!   

~ The Weather Channel 30-Day Weather

~ The Weather Channel Garden Tips

 ~ First/Last frost Dates by ZIP code from DG: 32º F, 28 º F and 24 º F. 10% to 90%


Climate Zones:

~ Sunset Climate Zones

~ USDA Hardiness Zones (average winter lows)

Koppen Climate Classification System

~ Koppen Climate System in Wikipedia

~ Koppen Climate System

~ Download Maps

~ Many Koppen Maps

  ~ Koppen Zones by County



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Fluorescent Bulb Types
Posted on Feb 1, 2013 9:27 PM

Fluorescent Bulb Types


Standard old T-12 fluorescent bulbs like shop lights emit 2 ½ time s as much light per watt as incandescent bulbs.   It's true: incandescent bulbs  are less than half as efficient as old fluorescent bulbs.  Use incandescents for heat.  Use fluorescents for light! 

The newer style, called "CFL" for Compact Fluorescent Bulbs, are much more efficient than old T-12 fluorescents.


 - T-12 bulbs are 1930s technology.  T-12s are dimmer and much less efficient than modern CFL bulbs.

 - T-8 bulbs (early CFL) are much more efficient than T-12s and a little brighter. Their price is now dropping to match T-12s.

 - T-5 bulbs (newer CFL) can be twice as bright as T-8s and about as efficient.  T-5s are more expensive per tube, but around the same price per lumen.


 - Old-fashioned 4-foot T-12 tubes consume 32 or 40 Watts of electricity and they only emit 2,100 to 2,800 lumens. They are the least efficient and least bright type of fluorescent bulbs.   (There are newer, higher-rated T-12 bulbs that go up to 3,200 lumens, but they are more expensive and less efficient.)


You shouldn't use the new CFL tubes in old fixtures because they need different ballasts.  CFLs need electronic ballasts and T-12s need magnetic ballasts.  Some websites and books say that you CAN run T-8s in a T-12 fixture "since the pins fit", but it's bad for the bulbs and inefficient.  


- T-8 bulbs use only 28 - 32 Watts of electricity.  T-8s are  much more efficient and somewhat brighter than T12s.  I see light outputs of 2,725  to  3,000  lumens.

 It looks to me as if the newer T8 CFL tubes are coming down  in price to equal the T12 bulbs.


 - Some T-5 CFL tubes are almost twice as bright as T-8s - they use 54 Watts but put out 5,000 lumens.  This is a cure for spindly, leggy seedlings! 

There are "High Output" T-5s and "High Efficiency" T5s, and others with unusually long lifetimes.  Special features cost more. 

T-5s are still evolving and falling in price.  Some T-5 bulbs cost up to twice as much as T-8 bulbs, but they do emit twice as much light.  It may be worth paying the shipping if you find a good price online for a case of T-5s with just the features you want.


Color, Spectrum or "Temperature"

 Pretty much any type of tube can be found in any color "temperature" (any spectrum) - cool blue, warm red, white or daylight.  Light that is too reddish sometimes causes elongation.  But don't spend money on "spectrum" at the expense of brightness.  Brightness (intensity) is more important, and it comes from lumens, plus closeness to the plants, plus good, clean reflectors.


I plan to continue using one cool blue and one warm red tube to cover both ends of the spectrum at least cost, greatest efficiency, and better bulb lifetime.  


Broad spectrum "grow-tubes" (tri-phosphor coatings) are a little different from color.  Broad spectrum tubes have tri-phosphor coatings to "spread out" narrow spectral peaks.  They have a more uniform distribution of intensity all across the spectrum, instead of sharp peaks and low valleys.


I've read that really expensive grow-tubes are just moderately expensive "broad spectrum" tubes that were re-labeled with marketing claims.  Both broad spectrum and grow-tubes are less efficient, more expensive, and don't last as long as regular tubes. 


It's debatable whether broad spectrum tubes do any better for seedlings at all.  I believe that chlorophyll absorbs it all and turns it all into energy (except for the narrow green band that makes plants look green).  But there may be seedling subtleties that I'm unaware of.


Tube Lifetime


Any fluorescent tube becomes less efficient as it ages, and less bright.  The rule of thumb with T-12s used to be "replace every 2 years if used 18 hours per day".  "20,000 hours" is claimed, but at the older age,  they give dimmer light and wast more electricity.  You should replace bulbs before they develop black spots, or flicker, or fail! 


If you put new bulbs into one fixture and you can tell by eye that it's significantly brighter than another fixture with old bulbs of the same "color", it is time to replace the old bulbs. 


Even if some intense but old T-5 bulbs are still bright enough to keep seedlings happy, at some point the saved electricity will pay for new bulbs.  At some later point, the saved electricity will pay for the cost of new bulbs PLUS the resources consumed to produce and recycle them.


How to get more brightness without replacing bulbs?  Clean the tubes and reflectors!  Move them closer to the plants more often.  Hang more reflectors down the sides and ends of your trays (but keep good air circulation).





Modern CFL bulbs have only around 3 milligrams of mercury per 4 foot tube.  That's less mercury than would have been released from burning enough coal to power incandescent bulbs!  But it is still mercury, which is very toxic. 


Many states don't consider 3 mg enough to call it "toxic waste", but YMMV.   There are eco-friendly CFL bulbs with 1/3rd the mercury (1 mg per bulb). I assume there is some trade-off in brightness, efficiency or longevity.  T-5s are still being improved, so read the fine print and watch for new models.


- -

T12, T8 and T5 stand for the diameter of the tube in eights of an inch.

T12 are 1 ½" in diameter.  Twelve eights of an inch add up to 1.5 inchs .

T8 bulbs are 1 inch in diameter.

Narrow, bright T5 tubes are only 5/8 inch in diameter.

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