Hey all! I'm currently dealing with conflicting info online and hoping you guys will guide me in the right direction. My question is regarding when to start adding nutes in rdwc? Some sites suggest starting once seedlings are 1-2 weeks old, while others state that to wait until cotyledons die off (week 3-4). Then there are some who say the cotyledons will yellow around week 2. Others suggest starting once the first set of true leaves appear. I'm aware that nutes should be started at 1/4 the recommended strength, I'm just not sure what age to begin?
When to begin nutes in rdwc
- Thread starter 420Mn
- Start date
ProPheT 216
Well-Known Member
As soon as u see the crown of the first 3 finger leaves/3rd set of leaves.
Please excuse my newbie ignorance, what do you mean by crown? And when you say third set of leaves does that include the cotyledons?
ProPheT 216
Well-Known Member
Yes including cotyledons.
As soon as u start to see another set of leaves growing from this stage. Kind of looks like a crown. Give them about ¼ strength feed the first week then up 2 half strength for a week then ¾ and stay there unless your plant shows deficiency. ¾ is usually right. Full strength as the label instructs you is usually to much.
As soon as u start to see another set of leaves growing from this stage. Kind of looks like a crown. Give them about ¼ strength feed the first week then up 2 half strength for a week then ¾ and stay there unless your plant shows deficiency. ¾ is usually right. Full strength as the label instructs you is usually to much.
Thanks man! And this goes for hydroponics as well right? My seedlings have their 4th set of leaves crowning (3rd set of true leaves). Thinking I will start at 1/8th the recommended nutrient dose and if all looks good tomorrow I will add another 1/8 to bring it to quarter strength.
amneziaHaze
Well-Known Member
I start dwc with 1/3 strenght day 0 (masterblend)and i do top feed for a week.then as soo as ppm start droping i give it more
Thanks for your input! It's good to hear that someone is starting nutes from day 1 with no ill effects. Your response set my mind at ease about starting nutes today. Thanks again!
shishkaboy
Well-Known Member
Are the roots touching the water yet?
amneziaHaze
Well-Known Member
I wrote in my diary somewhere what was day 1 amount
A couple have a few or more roots touching or in the water with more roots poking out the bottom and side of the netbaskets, while the other two have a couple roots in the water with more poking out the baskets.
I'm using reverse osmosis water which is void of calcium and mag. Should I start cal mag at 1/8 to 1/4 of the recommended dose or start with a full dose?
My concern is that it's required to use calmag or other alternative when using ro water as the water has no calcium or mag. And feeding chart shows that with ro water calmag should be used when starting nutes in the seedling stage. You think it's best I hold off and keep an eye out for deficiency? If I recall correctly, having no calcium and mag in the water will prevent plants from taking up nutrients? I could be wrong about the last statement as my brain is mush from all the research I've been doing (and the green I've been blazing).
OldMedUser
Well-Known Member
Your nutes have adequate Ca and Mg to start off with. I've done about 50 grows in DWC and always started my seedlings with 1/4 strength nutes. When you use a medium that is devoid of nutes you have to have something for the tiny plants to feed on as soon as the tap root pops out of the seed for optimal growth. No waiting for any of that other BS. Fine to wait if you sprout a seed in real soil as it has lots of nutes in it. I always started my seeds in those 9-hole seed starter pots filled with ProMix HP that were watered at the start with 1ml/L of each of the 3 parts of the AN 3-part nutes.
I would use CalMag at about 1/3 of the recommended amounts with RO water and never saw deficiencies tho would add some Epsom Salts as well at low doses until half way thru flowering when I'd add quite a bit more as the plant really wants more Mg, S and K in that stage. Less N and P after the stretch.
OldMedUser
Well-Known Member
If you have an airstone below the netpots the popping bubbles will cover any exposed roots even if they don't yet reach the water which should be about an inch below the bottom of the pots. When I would install the seedlings/clones into the system I'd just suck up some of the nute water and squirt if down the net pots once a day until roots emerged then stop top feeding.
I'd start at 300ppm which for the AN nutes was 1ml/L then as the ppm level would drop in the tub ad small amounts of nutes to keep at or raise teh ppm as the plants got bigger. I wouldn't change nutes until it was flowering time. Changing every week just throws away perfectly good nutes and makes the manufacturers of the nutes richer and you poorer. My last 20 grows or so I never changed nutes at all from start to harvest and had plants just as good. I did my first DWC in 2001 when nobody was doing it. At least nobody I'd ever heard of.
Your nutes have adequate Ca and Mg to start off with. I've done about 50 grows in DWC and always started my seedlings with 1/4 strength nutes. When you use a medium that is devoid of nutes you have to have something for the tiny plants to feed on as soon as the tap root pops out of the seed for optimal growth. No waiting for any of that other BS. Fine to wait if you sprout a seed in real soil as it has lots of nutes in it. I always started my seeds in those 9-hole seed starter pots filled with ProMix HP that were watered at the start with 1ml/L of each of the 3 parts of the AN 3-part nutes.
I would use CalMag at about 1/3 of the recommended amounts with RO water and never saw deficiencies tho would add some Epsom Salts as well at low doses until half way thru flowering when I'd add quite a bit more as the plant really wants more Mg, S and K in that stage. Less N and P after the stretch.
So are stating I should hold off on calmag or start it when I begin nutes?Your nutes have adequate Ca and Mg to start off with. I've done about 50 grows in DWC and always started my seedlings with 1/4 strength nutes. When you use a medium that is devoid of nutes you have to have something for the tiny plants to feed on as soon as the tap root pops out of the seed for optimal growth. No waiting for any of that other BS. Fine to wait if you sprout a seed in real soil as it has lots of nutes in it. I always started my seeds in those 9-hole seed starter pots filled with ProMix HP that were watered at the start with 1ml/L of each of the 3 parts of the AN 3-part nutes.
I would use CalMag at about 1/3 of the recommended amounts with RO water and never saw deficiencies tho would add some Epsom Salts as well at low doses until half way thru flowering when I'd add quite a bit more as the plant really wants more Mg, S and K in that stage. Less N and P after the stretch.
OldMedUser
Well-Known Member
A little won't hurt but whatever nutes you are using should have plenty of Mg and Ca as they are designed to feed the plants a balanced diet in a hydroponic system. So many people have it in their heads that if you don't have calmag their plants are going to die and use way too much which can end up killing their plants.
My nutes are designed for hydro but they state to use calmag if using ro water. Everything I've read on using ro water states that calmag is a must unless using nutes that are designed for soft water (ro). Not sure what to think now.A little won't hurt but whatever nutes you are using should have plenty of Mg and Ca as they are designed to feed the plants a balanced diet in a hydroponic system. So many people have it in their heads that if you don't have calmag their plants are going to die and use way too much which can end up killing their plants.
OldMedUser
Well-Known Member
Go ahead and use some but I wouldn't go over 1/2 the max amount on the label. I mostly used AN for 20 years and always used RO or distilled water. Our tap water comes from a dugout on my property and is about 400ppm and pH 8+.
Decent sized dugout as you can see from the pic I took recently with my new drone.
