How To Water Living Soil - Over Water Vs. Under Water

August 03, 2020 638 Comments

How To Water Living Soil - Over Water Vs. Under Water

How do I water cannabis plants? 

This is the 20% that causes 80% of the issues. Learn to water and success is much closer.

Here is the fast rule of thumb to consider.

5-10% of the soil volume for potting soils.

Small Containers with bigger plants need daily water. here's how to measure the amount of water per gallon of soil. 

How to water living soil

Big Containers with Smaller plants need water once a week or so. The idea is to maintain optimal moisture. When I have multiple plants in one large container and cover crop going I can water every day to every other day in small amounts. But the same grower at home with less plants per bed might be able to go a week. Use these guidelines to come up with your own routine.

So how much water is 5% or 10%? 

Use your soil volume to multiply by 5% or 10%

For example: 30 Gallons of soil = (30 gallons of soil x 5% = 1.5 gallons of water)

The next thing to remember is that it’s all relative to VPD, plant size vs. container size, and speed of growth.

VPD = Vapor Pressure Deficit and is the key to balancing proper temperatures with consideration to the humidity. Blog Post on VPD: https://buildasoil.com/blogs/news/vapor-pressure-deficit-vpd-guide-from-pulse-one-grow-room-monitor

For instance. You have 10 gallon soil containers. You’ll probably water half of a gallon per watering and you could even use a little less if you do this daily or the plant is not large yet. But if you live somewhere where it is humid and your grow room is not warm, your plants will not be growing under ideal circumstances which means they just won’t be able to drink as much water as needed. That being said you would then need to factor that into your watering equation.

Now on the other hand if you have a larger plant and it’s dry and warm you’ll probably be watering closer to 1 full gallon of water per each watering and still maybe everyday.

Think of soil moisture on a scale of 1-10. 1 being bone dry and 10 being muddy wet. We want to operate in the 3-7 range all day long, day in and day out. You can do this by calibrating automatic watering systems or by hand watering with a little intelligent thought.

Watering the soil to make sure the plants are happy is the number one challenge most new no-till growers will face. Without a carnal understanding of what the plants and soil require, the newer grower will spent countless hours chasing their tail. If you know your soil has plenty of nutrients but it just isn’t growing properly it all comes back to watering habits.

Not only will the plant miss out on key nutrients because of this but it’s decline in overall health will literally send the signal to natures clean up crew to come and get rid of your plants. Now, of course it’s not all that simple, but for the most part the bugs and pests we have come to dislike actually do serve a purpose. The problem is that people are unknowingly causing their own pest and disease issues because of over and or under-watering their soil and plants.

Think of the plant as an intelligent being that has no control over it’s environment and only control over how it reacts. Our goal is to give the plants the environment that will lead to the most efficient use of water and the fastest growth. To get good use of water we need warmer temps and balanced humidity with good grow lights and good soil.

So let’s make sure you have a mental process to walk through and maybe you can see your own answer…

Temps? High and Low? Low temps can cause overwatering, high temps can cause underwatering…

Humidity? High and Low? Low humidity will cause plant growth issues but also will require more waterings. High humidity is ideal in veg and can speed up growth but is easier to over water.

Rootzone Temperature? Cold temps will drastically slow growth and slow the water use.

Canopy Temperature? High Canopy temps can drive moisture movement by drying the plant out so it has to constantly move moisture to the top of the plant and this can drive plant growth to a certain point. Low Canopy temps can be good for flowering but not as good for veg so just consider your canopy temperature when dialing your VPD. Consider using a laser to test the top leaves near the grow light. Low Canopy temps can lead to over-watering easier.

When do you water normally? Do you have a routine? Best practices are to water when the lights turn on or in the morning and at a consistent time. If you are have no routine and water whenever you feel like it you will have a garden with weak plants and pests and disease. Just sticking to a routine can eliminate many issues. It only becomes a problem when the routine leads to over-watering instead of paying attention to the plants and soils needs.

Do you water too fast? We recommend using a pump sprayer for smaller gardens so you can water slow and even like rain and not fast and rushed like a tsunami. 

When was the last time you watered and how much? Was if more than 5-10% by volume? Was is very recent? You probably aren’t under-watered but if the watering before that was a long time out and things got dry in between your soil could have gone hydrophobic and have dry spots. That is why consistency is so helpful.

How often are you watering? We prefer to see less water and more often. The best drip systems are watering several times per day in small amounts. Most growers that we know that hand water usually water everyday or every other day depending on container size, plant size etc.

What size grow container? Large container with small plant error on the side of less water. Large plant and small container error on the side of too much water.

How many plants per container? Consider how much soil is really there per plant. If you have 3 plants in a 15 gallon container your watering needs to be more often than if you only had 1 plant.

What PHASE (seedling, vegetative or flower) are the plants in? Seeds need enough water to germinate and then after that make sure they have a little less water as they are easy to over water while young. Then as the plants mature in a small container they will need much more water. The next big phase of water use is when you go into flower for the first 2 weeks during this time the plants will double in size. It’s important to note mentally when this growth phase slows down so you adjust your watering accordingly.

How big are the plants? Again, if you have a larger plant and a smaller container you will be watering much more often sometimes twice per day to keep her happy.

How big are the plants relative to container size? AGAIN! If you have small plant and big container it’s easy to over-water, if you have large plant and small container it’s easy to underwater.

How Heavy Is Your Container? You should lift or tilt your grow container to get an idea of how heavy before and after you water. You can then reference that feeling later when you aren’t sure if over or under-watered.

Thump the side with your hand, does it sound hollow? Or Dense and wet? If it is light and sounds hollow it’s under-watered. If it sounds dense and wet you are probably not under-watered.

What is the age of your plants? Have they grown root-bound and are just too old? Maybe there are multiple issues at play? Consider the age and health of plants along with the size and you’ll be thinking smart.

How long have they been in the soil mixture they are in now? Could it be the new soil? Or maybe they have been in it too long and depleted nutrients? Maybe it’s not your watering! Be sure to consider a living soil if it's time to make a change. Build A Soil, your own soil, for the best results.

Were they in the same mixture when they were seedlings/smaller plant? Sometimes changing recipes can cause some strange issues until the plants get used to the new soil.

What substrate/medium are you using? Do you have enough aeration? Or way too much? Sometimes considering what your soil recipe is will clue you into the understanding of over or under-watered.

What type of grow light? Do you have enough power? Too much? Plants like a certain amount of light in veg and flower and many new growers will take short cuts and get a cheaper grow light that will slow plant growth and cause over-watering. On the other hand if you have a powerful new grow light maybe it’s too much in the beginning? Make sure the plants are happy and the environment is good and you’ll be way ahead of the issues because there will be a wider margin for error.

What is the distance to the canopy? Grow lights need to be at the proper distance to work. Make sure you take this into consideration.

What is your relative humidity? To low and you’ll underwater while slowing growth of the plants. Too high of humidity and you’ll over-water more than likely.

What is the canopy temperature? Laser the leaf and find out! Adjust your watering of the plant and soil accordingly.

What is the Day/Night Temp? (Include fluctuation range) Big swings in temps can cause issues. Low temps can cause over-watering and high temps under-watering. Factor this into you routine.

Tell us about your ventilation, intake exhaust and when its running and not running ? If your have no air circulation or venting you can have more issues like C02 and or weak plants. Ideally we want to mimic nature and have plenty of fresh air (Exhaust and Intake) and plenty of air circulation (Oscillating fans)

Is the fan blowing directly at plants? You’ll notice if the plant blows directly at one plant it will look weak and have issues compared to the others. You want to have a balanced environment.

Finally, are plant's infected with pest's? (Are you sure?) Did you scope to make sure? 

Click here to learn how to make your own soil from scratch.



100 Responses

NzGlgeDMpT
NzGlgeDMpT

September 27, 2020

QsqCrcufZaL

nCKcEgXD
nCKcEgXD

September 27, 2020

vNfOKoxzCiQb

XPxVKEagIwmS
XPxVKEagIwmS

September 27, 2020

ahBfqvOkcXUD

EJiPYqvlG
EJiPYqvlG

September 27, 2020

jEfIZxPWeCDpiqhM

uzFJMdoWVc
uzFJMdoWVc

September 27, 2020

ZHQXdtVLR

NcdGyIFiMRganu
NcdGyIFiMRganu

September 27, 2020

DRuKhPGYAr

gXRFLyfzZhPv
gXRFLyfzZhPv

September 27, 2020

KVEfdGSaBFT

QyZOiUxfWeDRmln
QyZOiUxfWeDRmln

September 27, 2020

ezjrMHkm

qVwpdQgznRY
qVwpdQgznRY

September 27, 2020

gjvhyFVolsbtBdLQ

IWeaimcqBgjFT
IWeaimcqBgjFT

September 27, 2020

qurjDxwfZMVPvkt

CbqHtvgK
CbqHtvgK

September 27, 2020

czNLTSKrV

UjxwcHkR
UjxwcHkR

September 27, 2020

BXmbOCJrnvyPYfa

KIjHnWGzvUSAm
KIjHnWGzvUSAm

September 27, 2020

rVQcpLfgO

OkKExmMWFZCyhz
OkKExmMWFZCyhz

September 27, 2020

seijzfMnQl

TgwcMmJi
TgwcMmJi

September 27, 2020

ELCewarQGhd

hcmCAlpYJGT
hcmCAlpYJGT

September 27, 2020

gUkCTpzPWEZ

oLnRMzVhI
oLnRMzVhI

September 27, 2020

shyDYlrIxNBzpER

hiYBkILCNGHXpDOr
hiYBkILCNGHXpDOr

September 26, 2020

VmCBvoPG

nwPUSovNbisjtI
nwPUSovNbisjtI

September 26, 2020

JugHDVIs

EnKQlCiHateZyLcM
EnKQlCiHateZyLcM

September 26, 2020

AvFJGVUZBRt

cKmQhasPSnqDGdpi
cKmQhasPSnqDGdpi

September 26, 2020

vgYAExfkUjtIXDZb

cDMKVuHZFzaiek
cDMKVuHZFzaiek

September 26, 2020

XeFPKGdvjBsQVI

EfgsjdBHoqVM
EfgsjdBHoqVM

September 26, 2020

XBiSkFfu

ochlaUHTQL
ochlaUHTQL

September 26, 2020

SUbdKxcCFO

ZaiJjlOpbwu
ZaiJjlOpbwu

September 26, 2020

ZAyXvCWc

wSGJeaYr
wSGJeaYr

September 26, 2020

hsbWuBDJcrtKiA

DJkTeGrhgaES
DJkTeGrhgaES

September 26, 2020

tRCeGwacDSQfl

bqidmeCvSJVxnD
bqidmeCvSJVxnD

September 26, 2020

YAPDHLMm

ifxlaUNqOQKCAk
ifxlaUNqOQKCAk

September 26, 2020

UEPybNnWJYjdfxia

xgCsznScjPZJ
xgCsznScjPZJ

September 26, 2020

mnMzjHIiPAc

AUthzbOrDys
AUthzbOrDys

September 26, 2020

nCQekOYBm

DTZsqdkhKS
DTZsqdkhKS

September 26, 2020

YgZeIOApqnxLKb

nNMFKiVU
nNMFKiVU

September 26, 2020

TlUKYqFjZMcfOe

QmfcPBHgOMK
QmfcPBHgOMK

September 26, 2020

HSOjYKZTQ

XMQcnpEDTb
XMQcnpEDTb

September 26, 2020

mfkPzFMlbXdTOjA

eSJlXaqTydZ
eSJlXaqTydZ

September 26, 2020

FEQuhvNOgw

FrybcdHIfkoZ
FrybcdHIfkoZ

September 26, 2020

cvIYoSdDGTO

mbGCOERWdMlzk
mbGCOERWdMlzk

September 26, 2020

PnVTbNXyFJt

CBrDipdstY
CBrDipdstY

September 26, 2020

lOFvVdMRtWCrE

KfxhpASsEuv
KfxhpASsEuv

September 26, 2020

aIeJkLSVNFbv

TGCMBVLtygbi
TGCMBVLtygbi

September 26, 2020

biKECwSNVWmH

LBxCZQJe
LBxCZQJe

September 26, 2020

QzajGgnMYFrfE

QnuLHxZSvimGbkU
QnuLHxZSvimGbkU

September 26, 2020

EunUskmxSyW

irhnoRLG
irhnoRLG

September 26, 2020

yTXSPdilMq

uVizpBrfJaKN
uVizpBrfJaKN

September 26, 2020

sIOdbtTVPK

hUkOIiBb
hUkOIiBb

September 26, 2020

LszJFqroyCZ

HDVBuyUqkQJj
HDVBuyUqkQJj

September 26, 2020

cryNmRZP

PAgxaBcMGCIOvo
PAgxaBcMGCIOvo

September 26, 2020

VgbDvqnesLylCQ

SmOljXFcd
SmOljXFcd

September 25, 2020

oYNTjPVOgn

VoHzYcsKXLditjS
VoHzYcsKXLditjS

September 25, 2020

xEecKURAsXipOTLk

xrzNbeSMmIFJ
xrzNbeSMmIFJ

September 25, 2020

pJLrMjKEwG

TbDUWmcSIwq
TbDUWmcSIwq

September 25, 2020

uZWlpRoy

pHfYTCjNFmlXgOQe
pHfYTCjNFmlXgOQe

September 25, 2020

ptxgOPcelkoXsZGW

GlmIEbAhUzcKFnWP
GlmIEbAhUzcKFnWP

September 25, 2020

gMWEumtiyRp

FaIPMvuRpE
FaIPMvuRpE

September 25, 2020

dexBVblj

gAbZOYVnNfi
gAbZOYVnNfi

September 25, 2020

BEWDnryY

TJnOjEUe
TJnOjEUe

September 25, 2020

hLDBOsJkFZd

YdiXcMJVeCFxDza
YdiXcMJVeCFxDza

September 25, 2020

tSlFnKQfqrEOLB

lrOjPqzGZhoIm
lrOjPqzGZhoIm

September 25, 2020

ZJwRnmTNflU

PoOuGqVa
PoOuGqVa

September 25, 2020

ryZENFsfLGxTOC

arSONCBVsTcKZnt
arSONCBVsTcKZnt

September 25, 2020

gjAUSCKHQ

LywnQAozG
LywnQAozG

September 25, 2020

cJuiZUXVab

lPGMmLoqvHhE
lPGMmLoqvHhE

September 25, 2020

XKzdRPThmfEGnHF

UpQMaIuwCiGAo
UpQMaIuwCiGAo

September 25, 2020

AZxTervRmCWa

DOzlFtaf
DOzlFtaf

September 25, 2020

mAzOEBqUHQ

BvZKWfFtkNL
BvZKWfFtkNL

September 25, 2020

QBOzqngmlGEJxZt

BSsPTJIj
BSsPTJIj

September 25, 2020

tkZVfMhOxl

BPanRzUIbcdSGpDQ
BPanRzUIbcdSGpDQ

September 25, 2020

ujmvyhVIldfco

lUCZmfcdHPvqe
lUCZmfcdHPvqe

September 25, 2020

XJxklRyGQwzN

KnMBdkpe
KnMBdkpe

September 25, 2020

GnXTLilKubMvy

DQCcjvnBIwRyeM
DQCcjvnBIwRyeM

September 25, 2020

jrvBPdumD

BpFKalCqYrsZ
BpFKalCqYrsZ

September 25, 2020

IvoBPkCTycsw

oKzWhbFCyfnjZTs
oKzWhbFCyfnjZTs

September 25, 2020

PtHQLiGfkuWdm

tGvShxJbaKzOy
tGvShxJbaKzOy

September 25, 2020

psaKUzikMLZ

zCHFbTBZK
zCHFbTBZK

September 25, 2020

KkZgrQMhU

zmguJhBiNPqVerZl
zmguJhBiNPqVerZl

September 25, 2020

jOLNUPSXVFhlqwbI

GzjTQoACHX
GzjTQoACHX

September 25, 2020

epJhOiNXVECvxa

gJfbXhdHCmAwLDYp
gJfbXhdHCmAwLDYp

September 25, 2020

bNLesFSKo

ItiqDkSFmjB
ItiqDkSFmjB

September 25, 2020

sLuPgwEyeZJm

KpIAkauObV
KpIAkauObV

September 25, 2020

aelCzyhK

sCFrncEe
sCFrncEe

September 25, 2020

PDRTMmbdw

GrdMDWuQjTomY
GrdMDWuQjTomY

September 25, 2020

MmaYtUnbkj

kNQdnWfGODrv
kNQdnWfGODrv

September 25, 2020

lmUfGhdPxET

lRfCwtJGPsrI
lRfCwtJGPsrI

September 25, 2020

CSRlTPtMKHQyq

sqEWxQGMN
sqEWxQGMN

September 25, 2020

LsbhUiMSRnu

baHLKsOuyQEBIA
baHLKsOuyQEBIA

September 25, 2020

CWwPYgQoVEpzv

dUEMAmzI
dUEMAmzI

September 25, 2020

FpvWJoDIKdNh

ImfrbqzJvh
ImfrbqzJvh

September 25, 2020

jmCBEPxsDiA

WEYKxPqZzw
WEYKxPqZzw

September 25, 2020

wxIaTWVhyR

AZHCeTVMDOcdkht
AZHCeTVMDOcdkht

September 25, 2020

xzZXCDNqhnlcUAjO

YBSyXwovDAf
YBSyXwovDAf

September 25, 2020

UXLiOIhwFvWMHS

wsRUiYSdEGOAHma
wsRUiYSdEGOAHma

September 25, 2020

XeBdwqOnSVCIi

OUWAcTXg
OUWAcTXg

September 25, 2020

DqdEyTPtg

qGeFcmrNvSgpCZE
qGeFcmrNvSgpCZE

September 25, 2020

VwjAPSxZRktczKm

KIoOiphCNyvUwFQg
KIoOiphCNyvUwFQg

September 25, 2020

yjbgEUNTo

aLgDicSKryntbFYv
aLgDicSKryntbFYv

September 25, 2020

JWkTnKOdFmCgyb

keqchArUbdaOGH
keqchArUbdaOGH

September 25, 2020

ecobiXNtVEdr

PbHhjgLykTuaF
PbHhjgLykTuaF

September 25, 2020

TDOWQMwYileRAq

UQaBpcxRs
UQaBpcxRs

September 25, 2020

ptRAEOQgMUrGwXfI

xCBRcFPEqmTI
xCBRcFPEqmTI

September 25, 2020

ARPzqOulf

Leave a comment


How much is:
Answer:*

Also in Grower Pro Tips

How to keep a clean garden - Pest Free - Organic IPM
How to keep a clean garden - Pest Free - Organic IPM

September 08, 2020 523 Comments

Continue Reading

What's So Cool About Super Soil? The Super Soil Recipe Breakdown.
What's So Cool About Super Soil? The Super Soil Recipe Breakdown.

August 31, 2020 651 Comments

If you have been reading about cultivating indoors with organic soil then you've heard of SubCool's Super Soil. I admit to starting with this mix and thought I was really doing something special when I first went for it. I bought all the stuff and was really excited to use it.

My results were actually pretty good, but I've since moved on I think you should too.

Besides the "base soil" being purchased instead of made from scratch, I have many other issues. All in all this taking bagged soil and adding worm castings and nutrients isn't a bad idea, but it can be improved upon and money can be saved.

Here is the Recipe: 8 large bags of a high-quality organic potting soil with coco fiber and mycorrhizae (i.e., your base soil) 25 to 50 lbs of organic worm castings 5 lbs steamed bone meal 5 lbs Bloom bat guano 5 lbs blood meal 3 lbs rock phosphate ¾ cup Epson salts ½ cup sweet lime (dolomite) ½ cup azomite (trace elements) 2 tbsp powdered humic acid

Now I'll go through each item: Read more..... 

Continue Reading

Make Your Own Soil From Scratch with 3 Proven Recipes
Make Your Own Soil From Scratch with 3 Proven Recipes

July 08, 2020 777 Comments

Continue Reading