Typical Blumat watering cycle?

[Ozmosis]

Hi. I would like to switch to a Blumat watering setup. I picked up a bunch of the Blumat Tropf stuff and set up a system in my yard for a tomato and pepper plant in containers in my yard. I decided to do my trial and error on vegetable plants rather than something more valuable. I got one of the Blumat digital soil moisture meters (tensiometer) monitoring my tomato plant that is a large growing Sweet 100 in a 10 gallon pot with good organic soil. I spent a week tweeking it including resoaking a carrot to verify I had all the air out. I am seeing larger swings than I anticipated. The plant is in direct sun over half the day and temps have been in the low to mid 80's outside. The tomato plant uses quite a bit of water at it's size and in the heat.
The best compromise I have gotten so far is as the pot dries over 100 the drippers start up and increase as the reading gets drier. It continues to increase in drip amount until the moisture meter finally tops out (dryness) around 160 - 170 Then the dripping rapidly slows and as the watering soaks in the moisture meter will drop (wetter) into the 30-40 area. I am shooting for a moisture level of 100 ish but I expected a tighter band of control. Could it be the fact I am using 5" carrots which probably only 3 inches or so into the soil, but am monitoring with the Blumat moisture meter which is about 6" deep in the soil? Or is this normal??

Details on the system.

Media: Organic: Soil
Container: 10 gallon nursery pot 17" diameter x 12" tall.
Type of water feed: Garden hose tap using 10 psi reducer made to maintain target pressure in static state (low or no water flow)
Carrot: 5" tropf carrot feeding 4 distribution drippers. 1st dripped about 3.5" from carrot
Monitor: Blumat Digital Moisture meter about 6" deep and about 3" from nearest dripper

 

[LordEnki]

Maybe try a Maxi sensor? 9" long, sensing moisture at 6ish inches deep... I'm rather new to Blumats, but I use Maxi's in my 10 gal fabric pots... If you're using standard sensors, maybe cut the first dripper back to 8 cm?

 

[Ozmosis]

I could put the maxi sensor in. The tomato is pretty big though at a good 6 feet tall so I imagine it would be hard to put a maxi in without tearing up some of the roots in the 10 gallon pot, which are likely extensive. Have you ever monitored your soil moisture with the Blumat moisture meter? I am curious if this kind of swing is normal or if I need to rethink the setup.

 

[LordEnki]

i have never used their moisture meter, sorry.

 

[Ozmosis]

i have never used their moisture meter, sorry.

No worries. Thanx for chiming in with your experience with them. Do you run 1 or 2 carrots in your 10 gallons? For 10 gallons I'd think 2 carrots and 4 or 5 drippers would seem about right. I'm thinking about using them in 7 gallon lined fabic pots later on if I can get a good feel for them on the vegetables.

 

[Jjgrow420]

I was going to ask what size your pot is and how many drip points
Position of the carrot is important. You want it in the middle not close to the side
What medium do you use? You need to take a reading about an hour or so after the drippers stop, and the moisture makes its way around the pot

 

[LeastExpectedGrower]

I was going to ask what size your pot is and how many drip points
Position of the carrot is important. You want it in the middle not close to the side
What medium do you use? You need to take a reading about an hour or so after the drippers stop, and the moisture makes its way around the pot

I was wondering if you'd end up here...

Yeah, I read through this and although I've used blumats on both cannabis & tomatoes, I'm not sure quite how to answer. I only used 1 regular carrot per pot (whether that was my .75g starter pots or my 5g bags. With tomatoes, they were pretty visibly damp and grew out of control. With cannabis in bigger 5g bags, often the soil around the stem would be visibly damp but not the stuff to the outside of the bags, but the cannabis didn't show any signs of underwatering even with that. I ended up feeling like somewhere between .5 to .75g per day was a good place to be, and wasn't terribly worried about any wet/dry cycle.

 

[Jjgrow420]

They're a bit tricky, and takes a bit of experimenting to get the right setting. The moisture meter is going to help.

 

[Jjgrow420]

I was wondering if you'd end up here...

Yeah, I read through this and although I've used blumats on both cannabis & tomatoes, I'm not sure quite how to answer. I only used 1 regular carrot per pot (whether that was my .75g starter pots or my 5g bags. With tomatoes, they were pretty visibly damp and grew out of control. With cannabis in bigger 5g bags, often the soil around the stem would be visibly damp but not the stuff to the outside of the bags, but the cannabis didn't show any signs of underwatering even with that. I ended up feeling like somewhere between .5 to .75g per day was a good place to be, and wasn't terribly worried about any wet/dry cycle.

I'm still learning things with them. They seem to work best in a living soil type situation where you aren't really running a wet/dry cycle or coco where you kinda want the medium wet all the time. Promix I find can be finicky because it wants that wet dry cycle,. Works fine in veg and early flower but can cause some problems later in flower I find. Still experimenting. Hard to tell someone what to do exactly when everyone runs diff pot types, sizes, diff medium etc etc

 

[LeastExpectedGrower]

They're a bit tricky, and takes a bit of experimenting to get the right setting. The moisture meter is going to help.

In my last run, where I moved to the Tropf Blumats from week 4 of veg through harvest, even with fussing with drip settings and/or having a hard time dialing in nutrient strengths, I ended up with at least as much final weight on my harvest...and actually a bit more than I'd been getting with hand-watering.

When I pulled the root balls out of the soil, I found that they didn't necessarily extend as far out as I was used to seeing, but were especially dense where the dripping was happening. That probably won't surprise anyone who's used them, the plants put out more fine roots where the water is and just don't extend where things are dry.

 

[Jjgrow420]

In my last run, where I moved to the Tropf Blumats from week 4 of veg through harvest, even with fussing with drip settings and/or having a hard time dialing in nutrient strengths, I ended up with at least as much final weight on my harvest...and actually a bit more than I'd been getting with hand-watering.

When I pulled the root balls out of the soil, I found that they didn't necessarily extend as far out as I was used to seeing, but were especially dense where the dripping was happening. That probably won't surprise anyone who's used them, the plants put out more fine roots where the water is and just don't extend where things are dry.

Yea I noticed smaller root structures... Me no likey that. Lol

 

[LeastExpectedGrower]

I'm still learning things with them. They seem to work best in a living soil type situation where you aren't really running a wet/dry cycle or coco where you kinda want the medium wet all the time. Promix I find can be finicky because it wants that wet dry cycle,. Works fine in veg and early flower but can cause some problems later in flower I find. Still experimenting. Hard to tell someone what to do exactly when everyone runs diff pot types, sizes, diff medium etc etc

I think I'll be reserving their use to times where I'm away for more than 4 days. I honestly like doing my own watering though it was also fun to set up and work with a reservoir system too.

 

[Ozmosis]

I was going to ask what size your pot is and how many drip points
Position of the carrot is important. You want it in the middle not close to the side
What medium do you use? You need to take a reading about an hour or so after the drippers stop, and the moisture makes its way around the pot

Hi

My pot is plastic nursery pot 10 gallon. I have 2 of the 5" tropf carrots. The main carrot driving 4 drippers is about 2-3 inches from edge of pot. First dripper is about 3" away then the other 3 drippers ring the pot about 2-3 inches from the edge and about 7 inches apart. One more single carrot sits near the center of the pot and the stem of the plant and only has it's own dripper being used. The moisture meter is about 1" from the 1st carrot and about 3" from the edge of the pot.

 

[Jjgrow420]

Hi

My pot is plastic nursery pot 10 gallon. I have 2 of the 5" tropf carrots. The main carrot driving 4 drippers is about 2-3 inches from edge of pot. First dripper is about 3" away then the other 3 drippers ring the pot about 2-3 inches from the edge and about 7 inches apart. One more single carrot sits near the center of the pot and the stem of the plant and only has it's own dripper being used. The moisture meter is about 1" from the 1st carrot and about 3" from the edge of the pot.

Hi!
Ok, what Medium are you using?

 

[Ozmosis]

Sorry for the late reply, I work 2nd shift. The medium is organic potting soil, more specifically G&B Organics Blue Ribbon Blend. It's not the be all end all organic soil, but it is a very solid soil.
Ingredients: Peat moss, recycled forest products, coir, pumice, rice hulls, composted chicken manure, bark fines, hydrolyzed feather meal, dried poultry manure, bat guano, kelp meal, worm castings, alfalfa meal, dolomite & oyster shell limes (as pH adjusters)
Then there is layer of generic compost on top of the soil about 1/2" thick.