Purplematic CBD - Focus on Soil Tests, Nutrient Levels, and Ventana Plant Science

[Aeromatics]

Here are some initial specifications for seeds, soil, nutrients, and grow environment:

Seeds: Purplematic CBD from Royal Queen Seeds

Soil: Sungro Black Gold Natural & Organic Potting Mix

Perlite: xGarden 8 Quarts Horticultural Grade Premium Perlite - Coarse and Chunky

Hydroton: Legigo Organic Expanded Clay Pebbles 4mm-16mm Lightweight Clay Leca Balls

Nutrients:

Root Boosters and Blends Great White Mycorrhizal Fungi Root Enhancer, DYNOMYCO Premium Mycorrhizal Inoculant, Mykos Mycorrhizal Inoculant, Tribus Organic Microbial Inoculant

Main Nutrient System: Ventana Plant Science (VPS), FlavUh, Stash Blend

Grow Environment:

Light: For Veg: Growers Choice ROI-FV-350, For Flower: Growers Choice’s ROI-FF-650

Tent: AC Infinity CLOUDLAB 844

Humidifier: AC infinity CLOUDFORGE T3

Ventilation and Circulation: AC Infinity CLOUDLINE T-Series Duct Fan 6 Inch and AC Infinity Duct Carbon Filter, Australian Charcoal, 6-Inch, AC Infinity CLOUDRAY A6, Gen 2 Grow Tent Clip Fan 6”

Pots: AC Infinity Heavy Duty Reusable Fabric Pots 3 Gallon

Goals for This Grow

SCIENCE!

No…really… it’s all about the science for this Purplematic CBD grow. In my last few grows, I noticed some issues with over-fertilization, drainage, small root development (even though I experimented with MYCOR and other root development projects, my root balls were still smaller than expected), and other general issues with my plants. While the quality of my GDP, Green Gelato, and Hyperion F-1 autos were solid, I know I was having problems with ultra-high TDS, and I really want to hone in my growing medium for these Purplematics.

So, I guess this grow is all about experimentation… but experimentation is a key component of science and I want to be able to fully utilize my nutrients (Ventana Plant Science, FlaVUH, and Stash Blend) while also working to hone in my soil test, aeration, and consistent TDS run-off measurement skills.

A final goal is to start recording long time lapses with a recently discovered GoPro Hero 4. I will be taking different pictures with a regular camera to document this journey, but I will also attempt, for the first time, a long form timelapse from different angles throughout Purplematic’s different stages. I hear this strain takes purple to a whole new level, and I think it will be fascinating to see in time-lapse form.

First Step: Soil Composition and Test

I soil-tested (equal parts soil and distilled soil mixed and soaked for 24 hours) a bulk batch of Black Gold and it came in at around 3000 PPM, which for my goals was way too hot. This is one of the first pre-grow soil tests I conducted, so needless to say, I already discovered why previous autoflower grows suffered from over-fertilization.

Since I want to be able to control my nutrient levels at different stages throughout the, my option is to amend this soil with perlite, and for the first time, hydroton. Some folks may argue that I should just use one or the other, but I thought, if I am really looking for increased aeration and additional nutrient dilution, why not use both. Heck… it’s an experiment! Haha

I wanted to create two different soil mixes (3-Gallon AC Infinity Cloth Pots) with two different starting TDS levels. Here is a table of my soil recipes as well as starting soil PH, TDS, Salinity, and Conductivity (EC):

Plant #	Soil	Perlite	Hydroton
#1	50% (12 x 500 ml)	40% (8 x 500 ml)	10% (3 x 500 ml)
#2	75% (18 x 500 ml)	20% (5 x 500 ml)	5% (250-300 ml)

Plant #	PH	TDS (PPM)	EC (Cond)	Sal
#1	7.06	460	.65	.32
#2	6.88	965	1.3	.68

As you can see (and stands to reason), measurements in soil test 2 were higher based on the proportionality of soil to perlite/hydroton. If I had to make a prediction, and this prediction will likely follow with intention, I will be using some more nutrient manipulation in Purplematic #1, as a TDS of 460 gives me a bit more room to play with throughout each phase of growth. I will also monitor #2, but assume that I will be using more nutrients during the flowering stages later in the grow cycle.

Germination and Sprouting

Germination was successful and the seeds were planted taproot down in each of the two pots. I cover my seedlings with a half-water bottle to act as a humidity dome, and the sprouts look healthy after 5 days of growth!

Purplematic #1

Purplematic #2

I plan on keeping my light at the appropriate DLI for Autoflowers, which is 12-16 for the seedling stage. I will be running 24-hours a day for the first two weeks, and then I will likely switch of 20/4 for the remainder of the growth. I have had good luck with 18/6 for autoflowers, but I am looking for a slightly larger-than-average yield.

What do you all think thus far? Any advice on feeding given my initial TDS levels? Anyone ever grown Purplematic CBD before?

[Budbrother]

Those 3K TDS numbers for the organic Black Gold are mostly unavailable. The meter can’t distinguish available from unavailable. You would find similar results from most any brand. Typically you don’t add salts to them for 3-4 wks.

[Aeromatics]

Interesting!

Based on that, how would I go about continuing to monitor my nutes, and is measuring TDS throughout the grow even important?

[Budbrother]

@Aeromatics

how would I go about continuing to monitor my nutes

Not my area. I run organics and don’t measure PPM or EC, since useless numbers to me.

@Aeromatics

is measuring TDS throughout the grow even important?

For salt growers it’s extremely important. You need to know the ins and out to determine feeding rates.

[Aeromatics]

Very cool! I’d love to learn more about organic growing. My dad and I used to grow strictly organic but he passed when I was 20 and, as any ignorant 20 year old does, I never took notes. Definitely a regret!

[Bonjoyle]

As BudBro said with salts or synthetic ferts, you need to monitor pH in, TDS or PPM’s in and in these initial stages, as long as the soil has 3-5 weeks worth of food in it, then you do not water to run off to check these 2 points on the out.. Once she has developed a bit, and you can start watering to run off, then that is when we break out the meters and start keeping track of the in/out and alter pH as needed and measure TDS/PPM’s to keep that target around 800-1000.

I did not see your water source mentioned. If using RO or distilled, then you have a blank slate and all TDS/PPM’s will be food. If using tap or something else the PPM’s in the water need to be taken into account when you start feeding.

PPM’s in the run off tell us if she is eating or not and if when checking the PPM’s and they are rising, then she is probably locked out even tho the food is there and that is usually caused by Ph being out of whack. Have you seen the Nute ph chart?

[Myfriendis410]

I will also point out that nutrient manufacturers are in the business of selling their product; not conserving it. You will find that “less is more” is a thing with growing cannabis.

Soil buffers differently and not uncommon to see a fresh batch of say, Ocean Forest, being in the 5K range. Native PH and good ingredients are the key factors at start.

Based on what you are trying to do I would suggest looking into coco/perlite so you are responsible for all nutes.

Different lines behave differently too: FF needs regular flushes. GH only at the flip for example. I’ve been running Jack’s with Autopots and don’t even bother monitoring runoff or flushing. Despite high salt levels late in flower, the plants respond well to it. I normally have a green, vibrant canopy at harvest (my preference).

You have some good growers backing you up.

[dbrn32]

I was reading through your post thinking the same things posted above already. Organic soils are typically loaded just waiting on microbial life to breakdown and make plant available. If you want to track and control fertilizers it would be better to be in hydroponic grow or using more of an inert media with synthetics.

[Aeromatics]

Absolutely! I feel like I am heading that direction if I want to continue to use Ventana Plant Science as my main nutrient system. I needed to start a run up before I leave for a trip later in the year, so I opted for this experiment.

I definitely need to look up hydro or inert medium with irrigation!

[Aeromatics]

Thank you, Bonjoyle!

That is 100% my plan for these two Purplematics! I’ll be very curious to see how the different starting TDS levels change once the plants start to settle into vegitation and hit those early flower stages.

I can’t believe I forgot to add what water I am using! It seems with every grow journal, I find one element I miss to share with you all haha… it’s part of the process!

I am using distilled water since I wanted to have as much control over my nutrients as possible without getting an RO system, though that may be in the cards in a future evolution. Here in CO, the water is incredibly hard and even my distilled water still has around 50 TDS on average.

I have looked at the nute table!

I will be using the top recommended chart for this grow (Soft/R.O. 0 - 150 TDS), and I will likely stick with even lower levels at the start, based on what I have learned, read, and what @Myfriendis410 says in his previous post here (thank you for that, by the way!).

I am working to have my PH between 6.0 and 6.3 for this grow. In my previous runs, I simply tried to get between 6 and 7, but I want to focus on narrowing that in to see if that has any real impact.

What do you all think?

[Bonjoyle]

We are neighbors Brother! I too am in CO in the Mile High.

[Aeromatics]

Awesome!!

I can’t believe we have another big snow on the way this weekend! So happy to have invested in my heater.

[Aeromatics]

Week 2 (Days 5 to 12): Stunted Seedlings and Adjustments

Well Week 2 is off to a rough start. It looks like I might have overwatered a bit and I am experiencing stunted growth and some yellowing seedlings across the board.

I upped my water of 500 ml after the first dose of 250 ml on Day 5. My first, and only, 500 ml water occur on Day 8, 4 days prior to these pictures above (Day 12).

Additionally, I upped my DLI to 16 for week two, but I felt like it was not enough given my lack of growth and water evaporation. I have increased it to 20/21 (250ish PPFD), and lowered my general humidity to 65%. My temperature also could have been a factor for these poor seedlings (averaging 72 degrees). I added a heater and we have been sitting at 77 degrees minimum for the last few days.

As a bit of an experiment, I removed #2 from the soil and carefully shook off the roots. I could tell there was still a great deal of moisture in there, so I fluffed up the soil a bit with some of the dry top medium and replanted. To me, it was worth the risk of seeing if I could salvage versus sitting and waiting. I have plenty of flower… so why not have some run!

With all of these adjustments, I am going to sit back and let them relax for a bit. Hopefully the damage is minimal and they pick up their growth this week. Definitely not an optimal start!

The good news is that they already look a bit better than earlier today (Day 12), so hopefully giving them another few days to dry out will be the way to go. Additionally, I am going to move back to 250 ml of water until they start to grow some more.

Any thoughts, recommendations or previous experiences I can benefit from?