Question about root mass in soil

Hey RIU - hope 2021 is off to a good start for all of you. I've got 3 runs now under my belt with autoflowers and I am still missing something when it comes to size and I think my root balls might be telling me something.

I recently harvested two Night Owl Spotless Mind plants that will maybe be ~30g dried each (pictures below). Both were in week 9 and started pre-flower around day 16. They just did not veg long at all - and their pre-flower stretch was short. When I pulled both root balls out of their fabric pots, I noticed volume wise, they only took up about 75-85% of the pot max. I've seen people whom have roots shooting out of the sides of fabric containers and that simply just was not these plants - so it got me thinking about how I water in the beginning seedling and early veg stages, and I wanted to run some of those thoughts by the Autoflower community here.

Here are some details on this past run:

• Container: 3 Gallon Smart Pots
• Medium: 60% FFOF / 40% Coco
• Lighting: Maxsisun PB2000 (205w) QB
• Tent: 2' x 4'
• Top-dress: Dr Earth Flower Girl [@ week 3]
• Microbes: Recharge [weekly], Big Foot Mycorrhizae [every 3 weeks]
• Teas: Roots Organic Bloom Terp Tea (dry) [x2 weekly]
• Bloom Boosters: Growganica Incredible Bulk (water soluble - organic) (0.1-10-21) [full flower week 1-3]
• Additional nutrients CalMag [once weekly], Molasses [once weekly]
• Temp: 78F (average throughout)
• RH: 54% (average throughout)

I went with a more organic approach and used zero synthetic nutrients aside from the CalMag I used but I wasn't too concerned with that - only used once a week in a 3ml/gallon dilution. The FFOF got the plant through the first 4 weeks no problem and then the top dressing done at week 3 took over along with the Roots Organic Terp teas I started feeding right at week 4. I started the bloom booster around week 5 and ended it at week 8. Recharge was given with one watering a week also. With this approach I also did not PH any waterings. The plants never showed signs of deficiencies through veg and into flower up until they started to fade out around week 8.

Here is how I approached watering and sprouting initially:

Started with a dry medium (not pre-soaked) -> planted germinated seed -> watered in 150ml of water -> waited for it to sprout -> watered in 150ml water -> rinse and repeat until week 2. Full soak week 3.

I am highlighting this because I think that I am screwing up the initial seedling / early veg watering somehow. I feel like my environment is locked down pretty solid otherwise. My plants never show signs of being under or over watered - but I think that my roots are just balling up around the center of the pot due to that being where the moisture is when the plant is a seedling / in early veg establishing roots. The roots never really grow out in search of moisture because they hit dry soil whilst they are sitting in the center of the pot where it's moist. I try to water in a 6in ring around the seedling initially growing outward until I do a full soak at week 3.

I am not starting with a pre-soaked medium and I suspect that maybe if the medium was slightly soaked before planting a germinated/non-germinated seed the roots would grow more outwards. I think this would be because they continue to grow out and find water within the medium, and therefore the root system continues to grow until it hits the fabric pot walls. I don't know just a thought. It's the only thing I can think of - I have a few more Night Owl and Mephisto strains right now that seem to be following the same path (which I will post pics of) right now and I have followed the above method once more.

I did as an experiment start two Mephisto plants in Fox Farms Coco Loco which I amended with a 3:1 mix of Roots Organic Bloom (3) and Veg Terp Tea (1) with a little bat guano and added 25% perlite. I pre-soaked the pots and let them sit for a day before adding my germinated seedlings. So far - I am at day 6 on these two seedlings and they already appear to be a little larger and growing a little faster at this stage than my previous grows with the FFOF / Coco blend. Have not watered yet since pre-soaking. Which kind of drove me to make this post - because it appears I have done it wrong prior to trying with these two plants.

up

bumppp

I use 3 gallon grow bags as well, have been for over 2 years now. I really love them!

Once my auto flower seed is germinated I place it directly into the 3 gallon grow bag. I usually only fill the bag half way to allow room to bury the stem some if it stretches more than I'd like the first 7-10 days. I fully soak the soil before planting the bean and then I don't have to water for about 10-14 days. For 2 weeks after that, the only way I water is pouring it into a plastic tray and letting the grow bag soak it up from the bottom up.

This seems to really help force the roots to search down for water. Not sure if there is any truth to it, but it seems like my plant growth is slightly better with this method.

TheDifferenceX said:

I use 3 gallon grow bags as well, have been for over 2 years now. I really love them!

Once my auto flower seed is germinated I place it directly into the 3 gallon grow bag. I usually only fill the bag half way to allow room to bury the stem some if it stretches more than I'd like the first 7-10 days. I fully soak the soil before planting the bean and then I don't have to water for about 10-14 days. For 2 weeks after that, the only way I water is pouring it into a plastic tray and letting the grow bag soak it up from the bottom up.

This seems to really help force the roots to search down for water. Not sure if there is any truth to it, but it seems like my plant growth is slightly better with this method.

Click to expand...

Thanks for sharing your method! I am going to try that out to see if I can improve the root growth. The two experiment plants that I started in pre-soaked soil (as you also experienced) are already ahead of any other seedlings at this age (day 8 now). My plan was to leave them alone for about 2 weeks, so the fact that you mentioned you do the same is awesome.

I will have to try bottom feeding / watering. I think it makes sense that this method will cause the roots to travel further down and out.

I'd like to add, this forum is filled with A TON of useful information. Sometimes you have to sift through the bickering and trolls, but if you focus on the posts that receive likes/thumbs up, you can really learn a lot here. 75% of what I know about growing was learned from here, honestly.

Also, starting a grow journal can help you keep track of progress as well as anyone that would like to follow along.