Flowering Dark Period: What is the Minimum to Begin Flowering Your Strain?

[Douglas.Curtis]

Hey

Like the title says, I'm looking for the minimum number of dark hours your strain needs to begin flowering. I'm interested in how wide the spectrum goes for photoperiod plants.

 

[BobMarley99]

14/10 should do the trick!

 

[Breadwizard]

I think it has to do with light intensity as well, 15 hours of weak light can set off some heavy indica genetics as well, seen it in my buddy's chamber

 

[Lost in a SOG]

Probably 10 if you use far red phytochrome initiation after lights out.

 

[Dropped Cat]

I flower 11/13 for a decent push. the narrow leaf types do
well, and the wide leaf hybrids acclimate to the light easily.

The set up is salts in coco hempy, PL L lights, micro size cab.

I recently over flowered a White Rhino to 90 days and still
only had 10% amber.

Veg is 18/6.

 

[djonkoman]

I grow outdoor, so I'm coming with some shorter dark periods as mentioned before. I write down the date my plants start flowering for breeding purposes.

this year, the date the first plants had visible flowering going on corresponds to a daylength of 16.40 hours(so 7.20 dark hours).

so assuming some delay between flowering being triggered and the moment I see first flowers, the actual flowertrigger might be an even shorter night.

 

[Douglas.Curtis]

I grow outdoor, so I'm coming with some shorter dark periods as mentioned before. I write down the date my plants start flowering for breeding purposes.

this year, the date the first plants had visible flowering going on corresponds to a daylength of 16.40 hours(so 7.20 dark hours).

so assuming some delay between flowering being triggered and the moment I see first flowers, the actual flowertrigger might be an even shorter night.

Awesome, ty What strains do you get this same response with?

Anyone else slowly increase dark hours on their strain and know when it starts flowering? Outdoor does this every year, and daylight/night hours have been published for decades. There were males in the region which began flowering almost 2 months ago. Some genetics definitely do not need 11hrs of dark.

 

[djonkoman]

What strains do you get this same response with?

these plants are some of my own crosses. so not something that's commercially available.

however, to donate earliness I've used early strains that are available, mostly HFH stuff but also some other early danish strains, but in an earlier generation some years ago. most recent earliness-donator was a wild super07 from HFH, and after that cross I've been seeing these plants that are properly early, the earlier cross with other early strains was still late(october finish, works ok in a good year, but that late is pretty risky around here).

I bet a lot of the HFH strains still beat my crosses in early flowering btw, but I never wrote down when those exactly started flowering when I grew them, I only exactly track my own crosses. also when I grew the pure hfh strains they were mostly at guerilla, so I didn't visit often enough to know when exactly they started flower.

There were males in the region which began flowering almost 2 months ago.

males do start earlier usually, something like 2 weeks. but start flower 2 months ago is what it's supposed to be, at least with the outdoor season we've got here, 2nd half september the risks start increasing. just found the first budrot of the season today for example. those plants I mentioned that flowered at 16.40 hours of light I have written down as start flowering seen on july 5th, so those have been flowering for over 2 months too.

 

[ambertrichome]

these plants are some of my own crosses. so not something that's commercially available.

however, to donate earliness I've used early strains that are available, mostly HFH stuff but also some other early danish strains, but in an earlier generation some years ago. most recent earliness-donator was a wild super07 from HFH, and after that cross I've been seeing these plants that are properly early, the earlier cross with other early strains was still late(october finish, works ok in a good year, but that late is pretty risky around here).

I bet a lot of the HFH strains still beat my crosses in early flowering btw, but I never wrote down when those exactly started flowering when I grew them, I only exactly track my own crosses. also when I grew the pure hfh strains they were mostly at guerilla, so I didn't visit often enough to know when exactly they started flower.


males do start earlier usually, something like 2 weeks. but start flower 2 months ago is what it's supposed to be, at least with the outdoor season we've got here, 2nd half september the risks start increasing. just found the first budrot of the season today for example. those plants I mentioned that flowered at 16.40 hours of light I have written down as start flowering seen on july 5th, so those have been flowering for over 2 months too.

If you want to add some really early flowering genetics to your mix, look into Vashon Seed Company Early Bird.

Its original Super Sativa Seed Club Genetics from the 80s, and is done last of Augus/1st week Septt, to Mid September at the very latest. Done in 6-6.5 weeks inside. Very good producer, and is extremely mold resistant.
James Bean Company has/had the seeds if still available, and they don't cost a lot either.

Early Bird was also known as M26

M26
An early Dutch cold-resistant strain. Inbreed for three generations. Breeding plants were selected for early maturation and quality of the high. Some individuals will have purple seed bracts. Most of the plants are very resinous. The yield varies from plant to plant. Harvest first/second week of September.

 

[djonkoman]

thanks for the suggestions, but with 6-6.5 weeks of flower I'm expecting a pretty indica type of high?
the whole reason I started doing my own crosses is to not only have reliable access to seeds that work each year(sources for seed have a habit of disappearing after some years, when the people behind it get busy irl or something), but also something that's sativa enough for my liking.
all the weed available commercially makes me fall asleep, I want something without couchlock. so I'm mostly looking outside the typical american/dutch indoor genepool.

for now I'll be focussing on stabilising the lines I've got, this year finally got some that flower at a time that's to my liking, but they do have a bit longer flowertime(one of those that started at july 5th is close to ready, but it just keeps on pushing out new pistils, so I'm leaving it for a bit longer). so next year I expect to be a lot closer to my goal.

previous 2 years I've still harvested plants in november(and I'll be doing that with 2 late flowerers too this year), without rot. after I crossed in kumaoni(from rsc) I got some quiet late lines, but the early plants now are also all kumaoni-descendents, a bit of early blood and some selection can do a lot.

I'm waiting for rsc to have the manipuri back in stock, and make a cross with that and see if I can get the finishing time down enough with some selection.

 

[Cvh]

 

[troutman]

I find some outdoors strains flower faster and don't need 12/12.

 

[Douglas.Curtis]

Though I appreciate all the "short" flowering info, I'm really only looking for the dark hours requirement from different strains.

If you know the minimum hours of dark for your specific strain to begin flowering, please post it. Tyvm.

 

[Albo_dingus]

Sept 23 is the September equinox and should be 12 and 12 in the widest swath of northern hemisphere and all hybrid and Sat will start many indicas will already be into flower

 

[Albo_dingus]

12 and 12 indoor

 

[Cvh]

I have heard that there are photoperiods that can flower when lighting drops below 16h.
And even extra early strains that stories say can start flowering at 18/6.

They were called fast finishers or early strains back in the day. But I have never grown them so I can't confirm the stories

With the rise of popularity of autoflowers I think they now got renamed to semi-autoflower. But they are not true autoflowers because they contain no Ruderalis.

 

[Douglas.Curtis]

I have heard that there are photoperiods that can flower when lighting drops below 16h.
And even extra early strains that stories say can start flowering at 18/6.

They were called fast finishers or early strains back in the day. But I have never grown them so I can't confirm the stories

With the rise of popularity of autoflowers I think they now got renamed to semi-autoflower. But they are not true autoflowers because they contain no Ruderalis.

Thank you, this is the type of info I'm looking for, thank you. I'm interested in where different strains are falling on the 'time flowering begins" chart.

I guess I should be asking who has the earliest semi-auto, yeah? But then... semi-auto brings up a different question, after reading the description for this strains.

When cloned and put under 24 hours of light you will see her start to flower within 2.5 weeks (autoflowering property)

There are semi-autoflowers which stay fine under veg lighting, but their clones auto flower?

Now I'm confused. lol

 

[Cvh]

Sem-Auto's previously known as Early strains (I think) were very popular in the colder areas in the EU several years ago. These were the best strains to grow outdoors before (Ruderalis) autoflowering were commercially available.
They were selectively bred photo's and not Ruderalis crosses.

But I haven't grown them back in the day, I was an indoor grower. So I can't confirm anything about the stories.

Sensi Seeds was the go to seedbank back then for Early strains. I think they still offer some Early strains ie. Early Pearl, Early Skunk,...

Here is also a description I found.

Semi-Auto Plant:
This refers to a plant that has some autoflowering traits or tendencies but does not always flower at a certain chronological age. The major difference between a true autoflowering plant and a semi-auto plant is that a semi-auto plant will be able to revert to a vegetative growth pattern under a 24h light regimen and even be grown into a mother and cloned, while a fully auto plant will not be able to achieve or sustain a vegetative growth pattern for any significant length of time. A semi-auto plant will usually start flowering with a reduction in day length, or when the roots get bound or when the food is changed to a flowering formula.

 

[djonkoman]

imo early strains should be distinguished from semi-auto. although early strains are indeed regularly called semi-auto too, but there's also the thing where an f1 cross where 1 parent is auto and 1 parent early(but not auto), that f1 cross is not fully auto but flowers earlier than the early photo parent.

the flowering from being rootbound I indeed also encountered with the early strains I've grown. keep them pregrowing in a small pot too long, and they'll start to flower. and reveg after planted out outdoor, but sometimes they can get stuck in a kind of half flower-half reveg.

 

[Douglas.Curtis]

Very interesting indeed.

Though there are other triggers than dark hours, I believe some of those semi-auto strains are actually early flower. I really wish I had the time to track down all the anecdotal and breeding history info. The root bound and nutrient triggers are also interesting, and I wonder what will come out of those in the future.

Do you know of any additional threads/sources which further explores this Photo x Auto = "Semi-Auto with unique characteristics"phenomena?