Self-regulating capillary mat watering (with budgie waterer)

[Vinlander]

It's worth looking at this photo in Allotments 4 All » Gallery » User Galleries » Vinlander » Capillary watering - Indoor capillary system - because the description contains how to make it and I don't know how to link it into the post. The close-up is also in the gallery.

I prefer this watering method because it is easy to make and it is low-tech throughout - almost no maintenance - almost nothing to go wrong - even in hard water areas. It is also cheap - though good capillary mat is worth buying and will last a lifetime - even so, you can buy 10x more mat than you'll ever need for the price of a high tech pump and solar cell (that comes with 10x as many failure modes).

I mostly use capillary matting on platforms sitting in troughs because I want to get the maximum light to the maximum number of seedlings.

You can see the space for a second 5L bottle, and how the mat is covered by non-woven black 'weed suppressor' - you can also see it doesn't completely stop moss & algae!   This mat system extends over and down the gaps along the the long sides of the platform so you can't really see that it dips in the water the full length of the trough.

The big plant is a 'Tahiti Lime' that survives very well with just a 'frost-stat' keeping it at 3-4C all winter - mainly because the mat system works on-demand - so it is never too dry or too wet. Citrus hate both extremes. Capillary even helps take water OUT of the pot if you've watered/fertilised from above (worth doing very occasionally when Spring approaches and demand rockets). My attrition rate for Citrus has dropped about 90% since I started using capillary. NB. Thick clay pots don't make good contact on their own - best to have some capillary straps with one end bedded in the compost up through the holes and the other end resting on the main mat.

I will cover the budgie waterer in the next post. And then maybe the outdoor system.

I also need to do some revision on how you link photo descriptions into a post! I suppose I could just copy it into the text...  Here it is:

Description: This is made from two thin T&G planks screwed through their bottom edge to either side of a heavier base plank, with a stub of 4x2 to close off each end - making a trough about 8cm deep lined with damp-proof membrane. The mat is on a platform made of real and/or artificial slates over supporting offcuts of paving slab (anything rotproof will do), making it about 1cm below the trough edge. The base plank was chosen to match the slates' width.

Cheers.

[Vinlander]

[Vinlander]

Here is the 5L budgie waterer holding 5kg of water above the clear 'trough' despite the hole clearly visible through the screwcap.



Description: Hopefully you can see the air space in the top of the 5L bottle showing that it is 90% full of water, with nothing coming out of the hole in the screwcap (until the level in the trough falls).

Here is a close up showing the water level - you can see that the water stopped coming out when the level in the trough covered the top of the upper hole (there is a lower hole in the other side of the cap).



Description: The bottle continues to hold all its water above the water level in the 'trough', but soon as the water in the trough is taken by plants the falling level will expose the upper hole to the air. It will immediately draw in air while releasing water from the other lower hole in the other side of the cap - and pushing the level back up. It's a demand-valve for water.

Here is a close-up showing 2 rusty nails through the 2 holes in the cap (each shows where the drill went right through the cap and the screw neck on that side but doesn't come out the other side of the cap).



Description: Note that one hole goes close to the top of the cap and the other goes close to the free edge of the cap. The height difference is crucial.

Keeping both holes within the cap makes it easier to hold them shut with finger & thumb when inverting a full bottle.

[galina]

I use the good old Geoff Hamilton self watering table system.  Where would we be without it!  I have described it a couple of years ago:
http://www.allotments4all.co.uk/smf/index.php/topic,78443.msg794247.html#msg794247
Mine differs very slightly from yours Vinlander in that my bottle is open and rests on two pieces of wood with the opening an inch off the bottom of the tray.  A 5 gallon bottle lasts for 14 days or more, but at least for 10 if it is very hot. 

Have added a photo - apologies for all the algae, the bottle doesn't look very nice at the moment 

[Vinlander]

Mine differs very slightly from yours Vinlander in that my bottle is open and rests on two pieces of wood with the opening an inch off the bottom of the tray.  A 5 gallon bottle lasts for 14 days or more, but at least for 10 if it is very hot. 

Does "my bottle is open" mean that it is open above & below? so does that mean it is drip feed rather than on-demand?

Cheers.

[galina]

Mine differs very slightly from yours Vinlander in that my bottle is open and rests on two pieces of wood with the opening an inch off the bottom of the tray.  A 5 gallon bottle lasts for 14 days or more, but at least for 10 if it is very hot. 

Does "my bottle is open" mean that it is open above & below? so does that mean it is drip feed rather than on-demand?

Cheers.

It is 'on demand':

I place the full bottle inside the tray onto the wooden blocks, with the stopper fully closed (it is very difficult to handle the heavy bottle with one hand over the neck to stop water gushing out when I invert it into the tray).  Then I unscrew the stopper in situ (there is just room enough to get my fingers in) until water can glug out of the bottle into the tray.  Doesn't have to be fully unscrewed.  There is no other opening in the bottle just the neck or water would flow continuously. The bottle is a standard camping water bottle or catering oil bottle with no modification. 

The water flow stops when the level in the tray rises above the neck of the bottle.  The 'tongue' in the capillary matting reaches to the bottom of the watering tray and takes up water on demand and transports it to plants on the table.  Capillary matting can transport water up to 4 inches to bridge the difference in height, and the drop from the table to the bottom of the gravel tray is less than 4 inches. 

When the plants use water and the water level inside the gravel tray falls to below the neck of the inverted bottle, air can get to the neck of the bottle.  This  causes another 'glug' of water to be released until no more air can get to the neck of the bottle, because it is now fully under water again.  No further air stops the water flow.  So it is an 'on demand' system rather than a dripper system.  During spring and autumn one bottle lasts two weeks and more, during the heat of summer the 5 gallons in the bottle only last 10 days. 

[Vinlander]

Hi Galina - thanks for the quick reply.

I was confused because I couldn't find the "Geoff Hamilton self watering table" anywhere on the internet. But then I couldn't find any demand systems on the internet - though there are hundreds of drip systems, and absolutely none of them can be trusted for 2 weeks in 'real weather' - no matter how many months you spend adjusting the nozzle or whatever.

What you describe is a good system - all on-demand systems are better than any drip systems. The on-demand ones that rely on fifty quid's worth (probably more) of sensors, valves, pumps, drippers and batteries/solar are good too - it's just that every high-tech component has about 20 failure modes of its own, and every component has to work or the whole system fails.

On the other hand capillary mats and inverted-bottle/budgie-waterer systems have very few ways to go wrong. Probably the biggest worry with my indoor ones is the strength of the shelf - but if it doesn't fail in the first week it's probably good for 2 or 3 decades. The outdoor one rests on a path - so no worries there.

Basically I'm happier with lo-tech - actually very, very, very low tech. I could use a hand-thrown pot from the early neolithic (or even a gourd from much earlier) with any textile or rush matting (also from earlier) or just a layer of peat over a puddled clay depression.

You could make a "steampunk" valve/sensor system with Victorian technology - it would be more reliable than hi-tech.

In fact I have one - my greenhouse capillary floor operates on the mains via a ballcock valve. Pity the ball is plastic - the original copper one corroded itself a leak.

There is one main advantage to having the water level directly below the platform with the mat on - you can't get waterlogging, even if you add extra water or fertiliser from above when it's time for the seedlings to have a richer feed - in fact the mat helps to quickly remove the excess water from any pot that has too much.

In nature all plants have (and "expect") a capillary link through the soil connecting with the water table below - most plants rely on this though some trees can send their roots down closer to the water table. Others (succulents) store water to cope with occasional breaks in the link. 

Basically my trough systems aren't primarily for holidays - I have plants/seedlings moving on and off capillary mat all year round, and it's good to be able to dose them individually against a background of perfect on-demand watering.

Incidentally I sometimes use pairs of corrugated 2L still water bottles on the portable system in my final photo - you can cut a cradle from one that holds the full bottle upside down firmly 5mm above the tray bottom - it is very easy to handle from tap to tray. You might find it useful - I'm writing this to remind me to take a photo of it.

Cheers.

[Paulines7]

Having seen lots of tips from Vinlander and others about how to make a water system that would keep plants moist during holidays, I began searching for some black plastic boxes.  Unfortunatey those I found were very expensive.  I then thought about the problem and have come up with a solution!

At the weekly market, the greengrocer throws out polystyrene boxes and I have been collecting them over the years as I use them to give extra protection to greenhouse plants during the winter, but this is another use that I have now found for them and solves my watering problem at the same time.

Instructions

Inspect the polystyrene box and ensure that it is watertight with no cracks or holes in the bottom.  Cut the lid so that it fits loosely inside the box and is about half an inch short at one end.  Measure and cut capillary matting the same width as the lid but twice its length. I use WaterWick matting by Gardman as it is good quality.

Half fill the box with water and soak the capillary matting.  Take the matting out and place 2 to 4* flower pots upside down in the water.  Put the matting on the lid with the long end going down into the water.  Lower the lid carefully until it sits on the flower pots.  Put plants in seed trays or flower pots on top of the matting and water them.  They can then be left until the water in the box is almost empty.  There is no need to take the lid or plants out to top up with water, as it can be poured in where the lid gap is.   

* The pots need to be big enough to be slightly above the water line.  The number required will depend on how big the polystyrene box is.