How to start a drip irrigation

hey guys i am going to be getting a drip irrigation going to start irrigation exactly like mr green to start seedling and small clones. My question is for those guys out their with this setup. Mr green was saying 3 times a day or more depending on if the blocks are dry or still damp, i know it depends on everybody's individual setup but how long do you guys run your pumps for when they come on? i have a 120 gph pump any input would be great guys! happy tokes!

come on guys!

10 mins an hour each day

Hydrochronic said:

hey guys i am going to be getting a drip irrigation going to start irrigation exactly like mr green to start seedling and small clones. My question is for those guys out their with this setup. Mr green was saying 3 times a day or more depending on if the blocks are dry or still damp, i know it depends on everybody's individual setup but how long do you guys run your pumps for when they come on? i have a 120 gph pump any input would be great guys! happy tokes!

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Rockwool is highly absorbent. If saturated, all oxygen, essential for root formation, is driven out of the material.

Very small plants in large (6") RW cubes or pots of RW floc may only need water every other day. Larger plants may tolerate watering 2x day. In all cases, flood durations should be short as RW doesn't need much time to wick up enough water to saturate. RW can be saturated if the plant in it is capable of removing about 50% of the water weight in 24 hours or less.

Drip feeding RW isn't such a good idea. Wetting the top surface with nute soln and allowing it to be exposed to light will guarantee a thick film of green slimy algae on the RW surface. RW works better watered from the bottom, either alone in a flood system or nested in pots of clay pellets which are watered with DWC or aero.

RW does not lend itself well to frequent watering. If kept saturated several times a day, overwatering symptoms will soon follow if the plant does not remove a large proportion of the water before watering again.

i am familiar with how rw works, i have had fabulous results with it soo far in my ebb and flow with pots of hydroton. I am thinking of drip for starting young seedlings and mothers as right now i just have 1 inch rw's. I think it would be easier than trying to find a happy medium with flooding the entire table.

I would not automate watering of seedlings and clones in RW cubes. That job is best done by hand. It would be very difficult to precisely apply the amount of water needed to dampen yet not saturate the cubes.

If you use 40mm plastic wrapped cubes instead of 25mm cubes, they will hold enough water to get a seedling or clone (before setting root) through 24 hours on a heat mat on one watering. Once clones set root, their water uptake rises dramatically- they'll need watered at 12h intervals. Cubes full of roots will tolerate being immersed, but before rooting or when housing a just hatched seedling, only need a corner of the cube dipped in a bucket to prevent putting in more water than the small plant will use in 24h.

40mm cubes weigh 5g dry and 20-25g when damp but not saturated, meaning they need 20-25ml of water per 24h. If you can automate a system which can precisely apply 20-25ml to each cube and sense when the cubes are getting too dry as roots pop and increase the water uptake, let me know.

I love to automate mundane op tasks whenever possible. This is one job that I've never found an acceptable substitute for doing it by hand.

wow that was awesome Al B. I have been having problems getting past the first set of leafs but i think my problem was my lighting though i had the seedling under one 15 watt cfl not nearly enough i think, my other room was being used so i was just trying to get get away with that until i could put under a 4 foot flourescent at least or my 250 watt Metal hallide. Is it okay to keep the cube on my heating pad or will it cause the cube to dry to fast? Thanks for your input AL.

I've used 25mm (1") cubes before and do find that they dry out too fast on a heat mat, needing 3 and sometimes 4 tiny waterings a day to keep them damp but not saturated. This is why I use the 40mm plastic wrapped cubes. Big enough to go a day on a heat mat and supply the clone but not too large as to hold more than 24h worth of water.

Work out the watering of your cubes by weight. Weigh a dry cube and note that figure. Saturate the cube and shake out water til no more shakes out. That's 'damp.' Subtract the dry wt from the damp wt. Since water weighs 1g per ml, You now know how many ml of water are in the cube when properly 'damp.' Put the cube on your heat mat. Weigh it every few hours. It's time to water again when 50% of the water wt is gone.

I doubt your 15W CFL was the problem, that's plenty of light for a seedling's first few weeks. Something else was going on. Overwatering is likely in RW cubes and would certainly cause stunting or death. Saturating cubes is a sure way to kill roots.

Hey al here is a pic of how i had my seedling set up underneath the tray is a seedling mat, and not pictured is the fan but that is the cfl i had on it, it only lasted 3 days after it broke surface. It looked like this before i went to bed, when i woke up it was all shriveled and kinda dark except the leaves. These 40 mm cubes you speak of what size is that 2 inch roughly? i've only seen the 1 inch ones at my store. These seeds are a nice blueberry x skunk #1 strain from the flying dutchman can't wait to them past the first set of leaves lol! Thanks AL.

Back the light off; seedlings and clones don't need much light. Was the cube saturated? Was the fan pointed right on it? Seedlings are very delicate things, really. They should get relatively gentle conditions until well established.

yes i did saturate only for about 20 minutes in ph adjusted RO water shock the excess off and used a spray bottle to dampen it when necessary from the bottom of the cube too. The fan was about a foot away. I did have the light 2 inches away

20 mins is farrrrr too long. Just dip a corner for a couple of seconds.



Raise the CFL to about 6-8" when they're really tiny sprouts. That'll do until they have their 1st or 2nd pair of 'true' leaves (3-5 bladed fans on stems).

Al B your sig makes me laugh, how old are you saying is grown up haha

I meant for initial saturation in ph'd water. This time i'm gonna use a 4 foot flourescent how high above should i hang it? I'll use your watering method too looks easier! i just weighed my cubes too and its 2.5 dry 22.5 damp so i guess that means 20ml of water to dampen the cube properly right?

HiGHLiFE28 said:

Al B your sig makes me laugh, how old are you saying is grown up haha

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18 and older. If you're old enough to die for your country, you're old enough to smoke what you wanna and cop it as an adult in court if you get caught growing it- in your OWN home, not anyone else's. Below that age, you're pretty much someone else's responsibility. You're allowed to make your own life hard, try not to make anyone else's hard.

Hydrochronic said:

I meant for initial saturation in ph'd water. This time i'm gonna use a 4 foot flourescent how high above should i hang it? I'll use your watering method too looks easier! i just weighed my cubes too and its 2.5 dry 22.5 damp so i guess that means 20ml of water to dampen the cube properly right?

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Oh, I see.

Hang the 4' also about 8" above the seedlings.

Yep, 20ml should be 'damp' but that's also how much water I put in my 40mm (~1.5") cubes. That might be a little much for the 1" cube. I might shoot for 15ml in the smaller cube. Check several times a day until you get an idea of how fast they dry out on your heat mat.

Alternatively to dipping (and more accurately) you can water with a syringe, a 60ml irrigation syringe is good for this job. Invert the cube and water the bottom if you use a syringe.

Great theory I like your style B Fuct

thats great Al i like your style too. Hopefully this all works for me everything else i have done has turned out great. I will follow exactly as you say! I'm going to have to train the wife while im at work to monitor our 3rd child lol. Thanks guys for the great info, i'm off to bed. later guys.

What about Hugo Blocks? I was told to saturate them in pH'd water overnight. How would the irrigation work for three of these in one dutch leach tray?

Thanks.

What's a Hugo block? What's a 'dutch leach tray'?