Another Irrigrigation Question

[BAYBOY]

Looking at varrious irrigriation systems for fruit trees. Have one year old mangoe trees in rows between canals with constant water all year round.

Have looked at sprinklers and drippers and similar. Have 450 trees but must keep costs in relation to expected income, so using sprinklers and drippers may be too much cost.

Has any one tried the black polythene pipe with holes spaced along the pipe? Is it any good and does it give good ground saturation? Used to be called "sokahose"

I know it comes in various widths 22mm, 31mm, and 38mm and rolls of 200 meters. Also does it last (being in the sun),for a reasonable time?

I don't have electric power on the land so have to use a Honda type pump 5.5hp from the canals.

Watering in dry season Nov/ April and wish to water tree radius which will expand as the trees grow.

Thanks. BAYBOY

[Maizefarmer]

Forget lay-flat tubing with preinstalled drippers – they will block over time (even if you have a disc filter installed at the head of the system) – often its alge that builds up in them, if not dust and dirt.

The problem is: cleaning them out (which means using a small pin or similar) often damages/destroys the flow mechanism in the dripper. The end result: over time you will have a tube full of drippers flowing at different rates.

Here what I suggest:

Semi-rigid ½” – 3/4” black pvc tubing – comes in rolls about 2m in diameter and around 100m in length. Lay it out down each tree row, and insert drippers longside each tree. Drippers can be purchased by the hand full from ag supply stores – they come in flow rates per hour of 100ml, 200 or 250ml, 500ml, 750, 1000ml, 1500ml, 2000ml, 3000ml , 4000ml …. all the way up to around 10litres per hour.

I reack on around 500ml per hour max. Why so low? – number of reasons:

1) You now don’t need to install a pressure pump – you can run low flow rate drippers like these from a storage tank under gravity pressure.

2) Been slow flow rates enables you to use a thinner irrigation tube without having to worry about pressure loss and difference between irrigation rates at start of tube length and end of tube length – the friction loss will be negligible over a 100m – 150m ¾” diameter will with 50 or so 500ml drippers stuck in it.

3) Low flow rates are excellent for fruit trees: the water gets time to soak in, and the water tension in the soil stays constant – good for root growth/distribution and as the soil is now always mosit, the tree doesn’t have to cycle its self through wet and dry soil time frames. Much much better for fruit yields.

4) Indiviual drippers can be replaced as and when required - no need to "cut and shut" as would be the case with layflat tubing with built in drippers

You need to install a storage tank – which you'd need to do in any case with lay flat preinstalled dripper tubing, so no additional outlay in any case - something like one of those ever so common circular concreate ring constructed tanks 2 x 3m diameter by 5m high tanks will be plenty: Reasons:

1) 5m high (down to 1m high water level when near empty) is going to give you all the water pressure you need to flow 500ml drippers along a 100 – 150m long ¾” tube.

2) No electricity/diesel expense now to run a pump constantly – big big saving!

3) Allows the water to settle – less dirt and dust into the system – less blockages in the drippers.

4) Always have a reserve of water.

You have one of those 5,5hp Honda/Kubota/yanmar portable type pumps? – that’s fine. Depending on how low the water is in the canal that should be fine to fill the tanks up in around 30minutes or so.

Tank construction – get it down properly – find someone who knows how to build them properly – other wise they just start leaking, the soil under the concrreate base becomes soft, it moves, then tanks lean …. And it’s a never ending problem, but they cheap to build and if built properly will last many years.

Anyhow - thats how I would go about it - no need to install a an hp system (high pressure) which will require ongoign energy costs to drive the pump - and as said , above there a lot of reason why slow flow irrigation is much better and healthier for fruti trees - so all round, replaceable drippers in semi rigid tubing has to be the way to go. Don't bury the tubing - place it in Y-sticks puched into the ground - this keeps the crap out the drippers and stops them getting damaged when the gofer goes round to clean the grounds, cut the grasss ect ect .............

Let us know what you decide to do - I'll detail you then on concreate stroage tank construction - so it gets done properly.

Edited March 24, 2009 by Maizefarmer

[teletiger]

Haha, you're going to be about 5 years too late with this next piece of info Maize.

Had a ring tank erected.....had heard of other leakage problems, so told the builders they wouldn't get paid 'til it was leak free for a month. Fine. Called them back 3 times before finally leak free. Paid. 2 months after I paid the leaks started. Called them back....no response. Called every week for 3 months...."very busy, but don't worry"...."Auntie just died"...."Yes, yes, we've not forgotten you" and on and on. Got someone local in to patch it up. It's been leaking on and off now for 5 years and looks a right mess. Only the front and sides leak. The back of the tank, facing East and protected by a windbreak has never leaked

Thinking about getting it moved, out of eyesight so eagerly await your revelations.

Regards.

P.S. Cost me 30,000 baht back in 2004. 2 mtr diameter, c. 6 metre high, 7 rings.

[IsaanAussie]

Haha, you're going to be about 5 years too late with this next piece of info Maize.

Had a ring tank erected.....had heard of other leakage problems, so told the builders they wouldn't get paid 'til it was leak free for a month. Fine. Called them back 3 times before finally leak free. Paid. 2 months after I paid the leaks started. Called them back....no response. Called every week for 3 months...."very busy, but don't worry"...."Auntie just died"...."Yes, yes, we've not forgotten you" and on and on. Got someone local in to patch it up. It's been leaking on and off now for 5 years and looks a right mess. Only the front and sides leak. The back of the tank, facing East and protected by a windbreak has never leaked

Thinking about getting it moved, out of eyesight so eagerly await your revelations.

Regards.

P.S. Cost me 30,000 baht back in 2004. 2 mtr diameter, c. 6 metre high, 7 rings.

TeleT,

Give this a try. Drain it out and get the inside as clean as you can, "paint" on a cement and water paste with a brush, two coats on the inside, two days to dry, refill and see what happens. It wouldn't hurt to include a good slug of waterproofing solution as well.

IA

Edited March 25, 2009 by IsaanAussie

[Maizefarmer]

Haha, you're going to be about 5 years too late with this next piece of info Maize.

Had a ring tank erected.....had heard of other leakage problems, so told the builders they wouldn't get paid 'til it was leak free for a month. Fine. Called them back 3 times before finally leak free. Paid. 2 months after I paid the leaks started. Called them back....no response. Called every week for 3 months...."very busy, but don't worry"...."Auntie just died"...."Yes, yes, we've not forgotten you" and on and on. Got someone local in to patch it up. It's been leaking on and off now for 5 years and looks a right mess. Only the front and sides leak. The back of the tank, facing East and protected by a windbreak has never leaked

Thinking about getting it moved, out of eyesight so eagerly await your revelations.

Regards.

P.S. Cost me 30,000 baht back in 2004. 2 mtr diameter, c. 6 metre high, 7 rings.

There you go .......... bang on the mark with that.

I know, I know .......... I see it all the time. There is defineatly an art to constructing these circular tanks - if the rings them selves are not constructed properly then they just leak and leak and leak.

2 points:

- the mix needs to be ratio'd correctly, and the right size stone/gravel has to be used - no skimping on cement powder

- they need to be "vibrated" when the create is poured into the mold -

.... both points I see constantly been missed out on during construction - result: pourosity in the setting - happens all the time.

[JungleBiker]

Looking at varrious irrigriation systems for fruit trees. Have one year old mangoe trees in rows between canals with constant water all year round.

Hi Bayboy,

I am just wondering if you really need irrigation? Once your trees are well established (perhaps by the end of this year?) won't they get the water themselves? The roots can go deep and depending on how far they are from the canals there is a chance that not too far below the trees there is water that they can tap into. Perhaps dig a hole in the tree row between two trees to see how the soil moisture is down below.

Furthermore, I understand that mangoes normally need a dry season of at least 2 months to get good flowering, so if they have water all year round (from the canals I mean, not from irrigation) then they may not flower well. Irrigation is good from flowering onwards but the canals may provide this requirement.

Best regards,

JB.

[BAYBOY]

Maize Farmer,

many thanks for the advice re the Dripper system and the using of the concrete tank. Please let me know the details re construction of the tank......thanks. Looks like the best way to go, and also most economical

By the way I read this fourum most evenings and always find your replies to faming questions interesting and helpful, as I am sure many others do.Thanks again.

..........

Jungle biker,

Thanks your comment. This growing of mangoes is a learning curve.Have read that they do need a "drought " period, and again that they love a regular and steady water supply.

About 30 kms from here there are several Thai growers who have switched from rice to mangoes over the last 10/15 years.Nearly all their orchards have 2 rows of trees seperated by a canal. The water height of the canals is almost to the level of the ground where the trees are, only inches, not feet below.

They also water by boats with pumps on, and flood the trees nearly all year round.The ground is always very damp and soft.Their trees are several years old.

Slightly off topic but again mangoes.Most of the local growers use hormones to boost the fruit which enables them to get 3/4 picks a year.

Any body know how this is applied ( sprayed on the trees or put into the soil) and is it a common practice here? Hard to get any answers to my questions from the locals. Some of these orchards are 30 plus rai in size. The best quality fruit is exported to Japan.

BAYBOY

[rice555]

Hello BAYBOY, I've used the product you described in your post and it works very well for some types of cropping, it has it's limits like fairly level ground. It uses the same 'low' pressure(0.8-1.0 bars) as thin wall drip tape. I used it between rows of papaya(2.5(2.0??) m O/C) and had nice coverage. I also tried drip tape(1.8-L/h) and Netafim bubbler's(24-L/H), they all had pro's and con's.

I think I posted a picture of the 'spray' tape(TS22) and fitting on another irrigation thread.

They also have a 65mm layflat manifold tape(100M) and fitting/valve to run you lines(31mm) off of it. It would be easy to make a small real to rewind the tape by hand as you walk along, the do the same thing for drip tapes, but that is all by machine and purged with air, 4/5 rows at a time.(row crops) for reuse.

The spray tape uses the same filtration as drippers or drip tape, but unlike the others, more holes is much easier to un-clog and or flush the tape if needed. We use to play in the water from green plastic sprinkler tapes 'like' this type 50 years ago when I was a kid.

As to the use you were going to use it for, i don't know, I don't water mango trees, there are some 4M-11M trees where I live now, I just fertilize a couple times a year's, I only like 1 of the 4 types here, the big tail likes them all, same as the jackfruit trees.

The catalog(paper) picture shows the tape being used under plastic mulch with row crops. I've only used the 22mm. It also will take 'light' abuse without damage.(punctures)(no kids, cows or tractors)

rice555

[Lickey]

2 years ago i had a 2300ltr clay urn made specially with a 1in and 2in outlets, deliverd cost was 700bht, it stands on a permanet concrete base as a reciever for the borehole pump, a luke loy elctric float starts the booster pump for sprinklers ect,

I had the same idea about concrete ring tanks, i think the quoted cost at the time was 35000 for a 5 ring tank, now thats a permanet fixture, at least with an empty clay urn, i can roll it anywhere i want on the farm,

I did set up a drip system on new papaya and banana plantation, but the first crop and the collecting trolleys and labour put a quik end to that,

I have seen local orange plantations with the pipe attached to the trunk, i would think this makes for easier strimmer cleaning round trees, but what i cant see from the road is if they have extension rubber pipes on the drippers, to keep the water away from the trunk which could suffer damage,

Forgot to add, the clay urn has had no problems at all, Just some more ideas for you Bayboy, cheers, Lickey..

[JungleBiker]

..........

Jungle biker,

Thanks your comment. This growing of mangoes is a learning curve.Have read that they do need a "drought " period, and again that they love a regular and steady water supply.

About 30 kms from here there are several Thai growers who have switched from rice to mangoes over the last 10/15 years.Nearly all their orchards have 2 rows of trees seperated by a canal. The water height of the canals is almost to the level of the ground where the trees are, only inches, not feet below.

They also water by boats with pumps on, and flood the trees nearly all year round.The ground is always very damp and soft.Their trees are several years old.

Slightly off topic but again mangoes.Most of the local growers use hormones to boost the fruit which enables them to get 3/4 picks a year.

Any body know how this is applied ( sprayed on the trees or put into the soil) and is it a common practice here? Hard to get any answers to my questions from the locals. Some of these orchards are 30 plus rai in size. The best quality fruit is exported to Japan.

BAYBOY

Hi Bayboy,

Actually the hormones is not at all off topic - it is very closely linked. I did say that mangoes normally need a dry season for good flowering. It means you can still get flowering without a dry season and there are other ways (besides drought) to stimulate flowering. One of those ways is to use pruning and a hormone or a spray of nitrate. All of this is explained in the attached paper. I hope you will find it helpful.

Best regards,

JB.

Off_season_flowering_of_mango.pdf

Edited March 27, 2009 by JungleBiker

[BAYBOY]

JungleBiker,

for some reason I can't download the file Off season flowering of mango.

Do you have another link to this download.

Very interested to read.

Thnks for your interest.

BAYBOY

[Maizefarmer]

Regards the concrete water storage tank. Well, as others very quickly noted, if this isn’t done properly it’s a mess – not to mention potentially dangerous (I know one person who has been killed and I know of others who have been given the fright of their lives – one guy only surving because he had just got into his pickup! - in both cases they had been smiling ear to ear only minutes earlier as they just filled up 5meter high tanks for the first time - yer, never mind the concreate, just think about that amount of water tumbling down in a rush on you!).

Base

1) dig out the soil 20” in a 4m x 4m square – then absolutely soak (fill the hole up with water and leave it to drain out, dry and then settle for 48hrs.

2) Throw in hardcore – any old hardcore for 8” – tamp it down.

3) Throw in 2” of 20-25mm granite gravel or similar – tamp it down.

4) Board up the edges of the 4m x 4m – about 2” above ground.

5) Throw in about 2” of concreate, lay a 6” – 8” square mesh (1/4” diameter) – peg it down with large nails bent into a u-shape to hold it flat, and throw over it another 2” of concreate. Lay down another layer of mesh and throw another 2” of create (i.e. ¼, ½, ¼ spacing).

6) Level it all off using a long 2" x 4" or similar, working in an arc from one crn, sweeping around 90degrees.

7) Alow a skin to form (takes a couple hours) – then (and this is real real important – do not skimp this part) – cover the whole throw with old sacks and wet with a hose pipe.

8) Leave them on and keep them wet for a good 5 – 7 days.

If you skip out on this the exthothermic rection during setting will drive out the water to fact and you will land up with brittle create which will not last – its why to see so many broken and cracked concreate pavements in Thaialnd – they don’t get the chance to cure them properly and slowly.

Note the above create mix should be no less than what we call in the trade a CP20 mix, which is: 1 x cement, 2 x fine sand, 4 x coarse aggregate. Now comes the important bit – how much water (get this wrong and you might as well pack up and go home): You want a “055” water mix – which means: multiply the cement in kg by 0.55 to get the amount of water to use e.g. 10kg of cement x 0.55 = 5,5litres of water. DO NOT EXCEED THIS AMOUNT OF WATER.

Tank

1) Go find a man with 3m diameter ring moulds – ask to borrow them, or stand over his guys when they pour he concreate into the rings.

2) Get 3” – 4” mesh (1/4” diameter rods), and spacers – cut to size and suing the spacers to ensure the mesh stays in the centre of the moulds (doesn’t touch the sides anywhere), put it into the mould.

3) Get the mix right – you want a very strong mix - what is known in the trade as a C30 to a C35 mix. Lets settle on a C35 mix.

4) C35 mix is: 1 x cement, 2 x sand, 1 x coarse aggregate

5) Now comes the important bit – how much water (again, get this wrong and you might as well pack up and go home): Take not if the sand and stone you are using is dry or damp – if its dry go for a 055 water mix, if its damp (as it could quite likely be if it comes out of measured weight plastic bags), drop it water to 045 (i.e. 0,45 litres per 1kg cement)

6) Add a waterproofing/or strengthening liquid to the mix in the final stages of mixing. Sold in most decent hardware stores, they all do the same thing – comes in a 500ml to 1litre bottle and looks milky white – follow the instructions, and for good measure add another 10%

7) Do a slump test – take a section of blue PVC water pipe measuring 4” diameter by 8cm high. Wipe the inside diameter with a oiled cloth and place it on the ground (level). Fill it with concreate from the concreate mixer. Pul the tube up and off the concreate – keeping it straight. If you aint sure you’ve kept it straight (which is why the pro’s use a cone), do it again.

8) The “tube” of remaining concreate should not slump more than 50% in height.

9) Your mix is ready to pour

10) Pour it all in one go – while a couple guys with broom sticks work there way round the ring tamping the concreate – stick the broom handle right in the mix and shake it up and down as they slowly move round the ring.

11) Fill the ring up – level off the rim, and scour a 1/2" - 3/4" deep groove into the top edge of the concreate ring using a piece of hosepipe or waterpipe

12) to achieve a centre line get someone to hold a stick in the centre of the circle - tie the section of hose/pipe to the stick with a length of wire (not string - it will stretch too much), and work your way around the top edge using this as a compass mechanism to keep on a true centre line. (I'll explain later why this groove is so important)

13) Cover the rim with wet sacking – wet the sacking a couple times each day.

14) Leave for a week – yes , week.

You now have concreate rings that will not break or leak – make and extra one and try breaking it – you’ll see just how strong it is if you have followed these tips.

Good Luck.

I'll explain next time round how join the rings together so the joints dont leak.

Edited March 27, 2009 by Maizefarmer

[BAYBOY]

Rice 555: re your reply the drip tape.

I think you are talking about the range of drip tapes from '"SUPERPRODUCTS". You used the 22mm tape,I had thought of using the wider 38mm tape.

Our trees are planted in 2 rows between each canal and are 4 mts apart between rows and 4 mts apart in each row.Would one roll of tape running down the middle of the 2 rows give good coverage around the trees, or may it need one roll per tree row.Follow?

Still looking at all options.

Checking prices and the making of concrete rings for a water tank.

Maizefarmer: again thanks for the method of making the base and the rings.............much appreciated.

Jungle biker: surprise surprise. We have planted the mango trees under the guidance of the local "EXPERT".I don't speak Thai and he of course, no English, except "very good." Have followed all his instructions totally and he confirmed today that we will be using Hormones to have off season mangoes. In the past I thought he was talking fertilizer when he was refering to hormone treatment. Hence the need for water through most of the year.

Still no luck getting your download on my computer.

By the way the "Expert" has 25 plus rai of mangoes and off one of his lots last week they took away 2 tonnes of fruit.

Thanks every one for the advice.

BAYBOY

[teletiger]

What does 1 of his "lots" consist of? Depending on age, 50 kilos per tree would be reasonable? I've heard of much more. 3/5 tons per Rai is normal. Our neighbour, who grows 15 Rai of very nice mangos...better than ours was offered 2 Baht per kilo...and she pays for harvest. After 6 weeks everybody in Pong Talong weighed 5 kilos more and was thoroughly sick of sticky coconut rice and yellow mango. You did check out your market right? Twice I've made that mistake. I might do it again next week . Thais believe in not buying land ( to live) beside a mango grove, or an orange orchard. "Too many chemicals"

Regards.

[BAYBOY]

Teletiger:understand that it was from 2 rai of 4 year old trees.

You have hit on a good point re.......... "was offered 2 Baht per kilo'. Sadly the grower is at the whim of the buyer and no-one knows the price until the buyer turns up at harvest.

Some 11 years when I first came here, on our land, the mother-in-law was growing Marfai (sometimes called Rambeh). That year price per klilo started at 22 Baht/kilo and dropped over the season to a low of 12 baht/kilo.

The local growers of Marfai do very little to the trees between harvest except giving a dose of fertilizer during the rainy season.Their orchards turn into semi jungle. Once the new fruit is flowering Nov/Dec. they tidy it up a bit, water often and when the fruit is golden they water the actual fruit on the trees.

The folowing year I kept the place tidy, almost weed free, fertilized, pruned and watered well, and even put sprinklers in the trees to water the fruit.We had fruit a week earlier than others, buyers calling and we started at 30 Baht/kilo.One buyer took the lot and the lowest price was 23 Baht/kilo. This effort continued for the next 5 years and the price lowest was 15 Baht one year due to heavy crops locally.

Left Thailand for 3 years and returned in 2006.Started where I had left off, again first on the market.. opening price 10 Baht/kilo which dropped two days later to 8 Baht and a week later 6 baht. Many many hours of work, fertilizer. fuel etc. ...and the buyer turns up, looks you in the eye 10 baht... heartbreaking.The pickers want 4 baht/kilo from you as well.

I am convinced the buyers work out the price well before harvest and know the grower has no choice. I do it for because I love the garden, an interest, and pocket money.I pity the grower who relies on his harvest for total income.

So as the marfai fruit is not popular with the young generation, liked by the older people, so demand going down, hence the move into mangoes.Sure the price of these will be up and down but the trick will be to have the fruit when supply is low and demand high. Most Thais love mangoes so the market is there.Also not to far from Bangkok where most of this areas fruit goes.

BAYBOY

[JungleBiker]

JungleBiker,

for some reason I can't download the file Off season flowering of mango.

Do you have another link to this download.

Very interested to read.

Thnks for your interest.

BAYBOY

Hi Bayboy,

Try this... http://www.scielo.br/pdf/bjpp/v19n4/a07v19n4.pdf