Perpetual Harvest, anyone?

Been reading, listening, getting the feel of the place for awhile, and I’m ready to ask:
Is anyone else out there running a perpetual harvest system? I’ve been doing PH since about '93; worked with a friend to sort out the kinks while in grad school, but now I’m thinking I still have more to learn; if I can find some (a few) kindred spirits with interest in PH, perhaps we can all learn a little.
I’ll be happy to detail my own foibles, epiphanies, and successes, if there is any interest, but what I’d really like would would be detailed comparisons with other DIY types, hoping to share the little “Eureka!” sort of gems of wisdom that such interchange inevitably uncovers…


@hydrograybeard things I have learned doing my own perpetual harvest:

  1. it’s much easier to do from clone than from seed so choose a few of your favorites as mothers to skip the germination process and have them ready to flower in 2-3 weeks instead of 6-8 and flower them according to flowering time as will be described next.

  2. when going from seed germinate seeds according to flowering time so you can finish a full tent at once after veg. So germinate the 12 week flower seeds first then 4 weeks later germinate the 8 week flower seeds. Then when you flower put the 12 week in first and let the 8 week veg 4 more weeks then throw it in the flower tent. Harvest a full tent at once and you can keep a rotation of both sativas and indicas going harvesting every 12 weeks.

  3. autoflowers are amazing for a quick turn around and can be left in the veg tent for small harvests every few weeks between the large photo harvest if timed properly. I’ve personally done 2 autos every 2 weeks so every 2 weeks once it gets going you’ll harvest a few ounces at least. This was with 8-10 week autos so i had roughly 8-10 autos going in the veg tent from seedling stage to flower stage with my mothers, clones, and veggers.

  4. even though it is tempting DO NOT pack more in than roughly 1 plant per square foot if sog because you will fight mold and humidity the entire time and have zero room to work around the ladies. Flower tent try to leave 2 square feet per plant unless you’re flowering clones as soon as they root instead of vegging them longer. Small clone sog can be 1 square foot per plant. Or if you do a 12/12 perpetual harvest with no veg 1 square foot per plant will work too. Plan for your tent/room size.

  5. potpourri is your friend. It’s cheaper than all of the pest control alternatives and works wonders. Just make sure you switch them out every few weeks when the smell subsides. I use cedar wood, lavender, and mint. Essential oils on cotton balls in mesh bags works too.

  6. water will get expensive so recycle as much as you can. I put my waste water in a solar still and reused it as much as possible after distilled. This works with drain to waste too as long as you have it all drain into a waste barrel that you can recycle.

  7. start keeping a compost pile and maybe even make a worm bin so you can get your own compost and worm castings because amendments and nutrients will add up fast. To cut costs and maintain organic growing (if you grow organic) do as much as you can yourself at home. The environment and your wallet will thank you.

  8. clean as you harvest with either vinegar, h202, or milk. I prefer milk and then I just wipe it out with water after i let it sit and do its thing. It will help in the long run and none of it is caustic so as soon as you finish wiping out the flower tent you can throw more plants in there without worrying about bleach or other cleaners. Gotta make sure you keep mold and pm under control.

  9. keep it fem and keep it sensimilla. Trying to breed in a perpetual harvest is risky unless you intend to seed the whole tent.

  10. keep it as small as you can just to meet your needs. Don’t get excessive with it. If you aren’t a commercial grower and selling it it isn’t worth the cost and effort if you go overboard just to have lbs at your disposal. I understand I stated I grew a lot of plants above, and I learned my lesson. :joy:

  11. have fun with it and don’t let a hobby become a burden. If it becomes too much, you’re doing too much.


@hydrograybeard as far as the DIY aspect I have details on how to make a home made solar still, home made compost tumblers, home made worm bins, home made organic pest control alternatives, home made nutrients, home made ethylene blockers (colloquially known as feminisng spray even though it forces pollen production), home made rooting solutions and compounds, as well as home made environmental control options for humidity and temperature.

It requires a lot of time to get everything going but not a whole lot of cash really. Once it’s all going though it’s fairly easy to keep fresh clean water and organic nutrients flowing.


Thanks for your prompt and comprehensive response.
I’ve been under the weather for a couple days; I’ll respond more completely when I get back on my feet.

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Back in '84-'89 I had two setups: one for cloning and veg and the other for flowering. The veg used four 4ft florescent grow lights and the flowering used four 4 ft florescent cool white bulbs. I usually had 3-6 plants in the veg at different stages of growth and 2 or 3 in the flowering room. I didn’t try to harvest a plant all at once like we do today. I harvested in stages.

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@Darodguy in the late 70’s early 80’s and up before T5 bulbs i grew pounds of weed with 4foot flourecent tubes. No one ever complained about my bud. it was $30.00 an ounce. everybody else was still stuck in that :point_right: going from $12 to $18 for an ounce of outdoor grown stuff

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Yep, that’s about how I started, back in the days of T-5 fluorescents. When I went to college I was introduced to HID lights, and the world changed! Lots of tales to tell from all that, best reserved to another time. About the time I graduated, I mentioned in conversation that I’d read it’s possible to go start to finish in 90 days. A friend, and probably the most experienced of my circle of acquaintances, responded, "Oh I don’t believe that!
Naturally I took that as a personal challenge, and it set my horticultural path for years to come.
Grad school at Colorado State, and a neighbor & fellow Grad next door was also trying to get a closet grow going; we shared tips & genetics for three years.
As to the challenge: 77 days, start to finish, with clones. No males in the house.


@hydrograybeard the old days were scary but wow was the excitement fun even though we had to stay two steps ahead of the fuzz busting us for what we loved. i could listen to those stories about the old days all evening long puffing with my friends. i can remember over a couple times that i had to tell myself. Dang, that was close, they almost got me LoL and it wasn’t just the cops every time. Friends asked, what did you do? :laughing: i said, it’s simple “i FLED!!”

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@hydrograybeard yeah. That’s with 8 week flowering plants. Used to do those clone runs myself. I tried one recently with those new fast flower varieties that had a 6-7 week flower time and finished a whole tent in 9 weeks from clone. 63 days. It was insane.

I went back to seed though because the breeding bug bit me again. Lol

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As you suggested, I’m doing this for my own use, and have refused MANY offers from eager buyers.
I use small containers (<2l), 100% perlite, pure topfeed hydroponic. Used Ecogrow from '93 to '19, when they discontinued my go-to nutrient.
Got fired up again last summer, and had a seed in a pot late August. After sifting through reams of nutrient systems propaganda, I’m trying to focus: Keep It Simple, Stupid! (Here I must confess to an unfortunate character flaw: I have a maddening propensity to things more complicated than they need to be. I have struggled with this most of my life.)
In the interest of KISS, I’m using gh flora system with hardwater micro, cal-mag+, phosphoric acid for down, potassium hydroxide for up, and well water at about 6.3/300ppm.

It’s late, I’m already worn down, I’ll continue responding to each of your comments at another time.

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Ok, Doc, here’s a bit more about my little perpetual system.
Got the basic idea from an old High Times, sometime in the early 90s: 2-liter soda bottles with the bottoms cut off, fitted to white plastic pipes draining back to a Reservoir.
An article about '92–93 in Growing Edge reviewed the article and constructed such a system… and tried to grow tomatoes in it, with unsatisfactory results, mainly because of blockage of the bottle necks with dense root growth, and many leaks.
They concluded that it is an unworkable idea.
I concluded that it was poorly designed in a number of aspects, but the idea itself is indeed workable, and remarkably flexible.
I can easily build a pipe rack fitted to any size or configuration of enclosure I find myself in, for about $7 - $8.
Currently, I’m growing in a 8 x 16 storage shed, with three enclosures therein:
1/ the veg garden is about 30" x 40" with connections for 30 pots. The design population is 18 plants, and the extra holes facilitate turning and moving the plants, gradually rotating them through the garden, which happens every day.
2/ The first flower garden is 33" x 42", with 12 holes and a design population of 9.
3/ The F2 garden is 36" x 48", again with 12 holes & meant for 9 occupants. Both flower gardens also rotate through all the holes.
The rest of the shed is filled with equipment and supplies, including backup air conditioner, and backup heater, timers, pumps, fans, and lights.
I start one seed at a time, 2 to 7 days apart.
After all the bugs and leaks and nutrient recipes and cultivar selections are sorted out (which, as you mentioned, takes a long time), and a few months down the line, I harvest a short, bushy mature plant every few days, producing 20 - 35 grams of primo sinsemilla. Like, 3/4 oz every other day!
I like 3 or 4 day schedule best; nice relaxed pace:
Day 1: harvest the next plant in line.
Day 2: take the biggest one in F1 to graduate to F2
Day 3 : the next (usually biggest) in Veg graduates to F1
Day 4: start a new clone
Using this system my longest run was for more than 18 months, with 159 clones without a failure, and a harvest of 2/3 to 3/4 oz every three days.

Enough for now.
More detail to share, including the redesign of the pipe racks and general operations, if there’s enough interest to be worth typing it out.
Comments, suggestions, cautions encouraged.
Best regards, AW


@hydrograybeard Really interested in a picture of your setup and the piping…save you lots of typing!

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Hey, Spud- Took my camera out to the shed when I went to do the daily chores, but when I started looking at the place through the camera, it became clear that some (a lot) cleanup will be appropriate before publication, as I’ve been making messes as fast as I’ve been cleaning up… and the F2 enclosure is dark right now for a turnaround anyway, and only 3 occupants in F1.
So… photos in a few days, probably.