Pereskiopsisdotcom wrote: ↑Tue Aug 20, 2019 7:04 pmHow long did it take you to figure out that this was the light for you? I assume you supplement with outdoor sources too? But until it gets degrafted from seedling to grafted it goes under your grow lights? And for someone with no electrical experience, I would have to find a friend to build these for me. Though I see individual LEDs are cheap on Aliexpress.
I apologize for the delay.
I have been started using LEDs light since Nov 2015.
Initially it wasn't for cacti growing, it was artificial light for spicy plants, for growing vegetables sprouts.
In that time I bought 50 small 'full spectrum' LEDs (3 unreal Watt for each single LED, actually it was the marketing trick, 3.0-3.2V * 600mA = 1.8-1.92W not 3W! ), as I pointed out, it was old generation of LEDs.
Those LEDs generally emit blue light with 445-450nmm wavelength. Part of that blue light pass through phosphor, and part of it is conversed into red light with maximum peak at 620-630nm.
Ratio of blue to red is approximately 1:3. Some people say those LEDs are good in flowering time for herbs, but bad in vegetation time.
People who experimented with different red LEDs, i.e. 620nm and 660nm, says that 660nm is better.
I never tried to use genuine 660nm LEDs, but today I have (not 100% sure because of Aliexpress goods
) new generation of 'full spectrum' LED that have phosphor which converse blue light into 660nm, it should be better.
I made two plastic grow-boxes and two lamps for each box. One box was bigger but today I use only small grow-box with small lamp, but big lamp I use without box.
Small box is 0.25cm width, 0.45cm length and 0.21cm height. It has approximately 0.11sq meters or 1.21 sq foot.
I have read many articles how much LEDs light should I have for each square meter.
My calculations said that ratio the electric Watts to the square meters was more than enough (if I will use maximum allowed electric current for LEDs):
Guess I have 50W lamps in means, so 50W / 0.11sq m = 444 W/m2 or 41.3W/sq foot
I had been started experimenting with LED light and grew some spicy herbs (Basil, Rosemary, Sweet Marjoram) from seeds.
Fortunately in that time I also had some cacti seedlings from my first time sowing and I decided to place the seedling under the LED light.
In the experiments with LED light that I have, I had changed the electric current, searched the optimal current regime. I had started from 600mA and reduced it to 350nm.
Hight current (500..600mA per LED) gave me red coloring stems of the plants. Even more, I have noticed that cacti seedlings had been reacted on light changing (i.e. current from the LEDs) much faster than herbs, and also cacti had lost red coloring withing a week-two if I decrease the light (electric current), but herbs reacted to decreased light much slowly.
In other words, cacti seedlings were indicator how much light I need to give them and whether was overlight.
Those seedlings
So, my important conclusion was "put cacti seedling (these were Myrtillocactus, Ferocactus and Carnegiea) under the light" and over-watch what/if there was any change on epidermis color.
I also seen someone's experiments with blue 445nm LED and 660nm red LEDs and ration blue to red was different that mine, more blue light, so the results were deep blue-ish coloring leaves of the succulents (Kalanchoe and Сrassulaceae succulent) and leads to very short distances between nearest leaves (short internodes) under such light.
So, I found out optimal electric current for LEDs in my lamp and went to sowing Lithops, Dinteranthus and Lapidaria in 2016. My succulents almost never seen sunlight before end of the Spring 2017.
In sunny days I regularly moved pots from windowsill to back under the LED lamp and have continued lighting to 9pm or 10pm. Then on the next morning I moved pots back to (indoor) windowsill.
In promising rainy or cloudy days I left the pots stay in grow-box under the LED light.
Summer and autumn 2018 I didn't use LED lamp and these succulents have been grew only under the sunlight indoor on windowsill.
Also, that time LEDs in my big lamp have been started to die one by one because of expired lifetime. But small LED lamp have been still worked. And I have been started my new search what was the new in cheap LED offers.
Late autumn 2018 Lapidaria had been going to bloom, but the days were too short to flowering. I moved the pot under LED light and flower tried to open at 8pm, but did it incompletely.
Next days were the same. Flowers had never opened fully under that "violet" LED light even if I use later two additional 10W Cold White LEDs.
So, my next conclusion was "violet LED light is not for bloom". Furthermore that extremely bright "violet" light gave me episodically headaches, my brain have never adapted to this wrong light, light without green component.
Jan 28, 2018
Dinteranthus, Lapidaria & Lithops before they've ever seen the sunlight that year
Old LED lamp construction. Actually it had 80+ small 'near UV LEDs' but they were useless.
Nov 10, 2018
'Lapidaria margaretae SH588' under LEDs was trying to bloom.
Searching on Aliexpress in Winter 2018 I found some sale promotions of old generation Warm White LEDs and new generation of "full spectrum" LEDs.
Because of my strongly disaffection to "violet" light, I decided to use "full spectrum" LEDs in the minority, preferring to use more Warm White LEDs.
But as I found out reading from many resources, cheap Warm White LEDs have less portion of 660nm light, so I still have to use either pure 660nm LEDs, or new generation of "full spectrum" LEDs.
My final construction of LED lamps haven't any complete explanation why was such amonut each type of LEDs, but have some logical background.
And what is most importantly - that construction give me good looking plants.
The new (actually, upgraded) LED lamps I used, as I told before, for growing cacti seedlings and later for grafts. Neither cacti seedling, or young grafts were never placed under the sun light.
I did the grafts in late Autumn and Winter, so it haven't enough sun light in that time. My grow-box with LED lamp is placed in room with tiny window, the light from the window have never fall in grow-box.
I have started move the grafts on windowsill in later Spring on sunny days, and anyway moved pots back under the LED lamp after 6pm, have continued lighting to 9pm or 10pm.
Some times later, there was a day that Loph. was going to bloom, but that day was cloudy. I placed L. under the LED and the flower has opened. That was a small victory.
April 2, 2019
There was another cloudy day that Frailea had promised to bloom. I placed that Frailea under the LED lamp but the flower has not opened.
That had no explanation for me.
So, we have come to the last secret. This is the distance from plant to panel with LEDs.
First construction of small grow-box had 21cm in height. Most of time there was a pot with lithops. They were flat as possible and never tried to rise higher as well as they do it in shady place.
The distance from lithops to LED lamps was 12-14cm. When I had necessity to place the pots with grafted cacti seedlings on Pereskiopsis shoots, I have increased the height of the box.
Thus the distance from grafted seedlings on the tops to LED lamp also became about 12-15cm (without increasing the height of the box the distance would be to small, approx. 5cm.)
And finally, here is the list on Aliexpress that you can reffer to build your own LED lamps.
1. Warm light LEDs
https://www.aliexpress.com/item/32786793252.html
Only 10W model hasn't on-boarded driver so it's more "flexible" on you own wish current-changing purpose.
2. Cold White LEDs
https://www.aliexpress.com/item/1363857929.html
I bought 'real 10W' item.
3. New-generation 'Full spectrum' LEDs
https://www.aliexpress.com/item/32958493220.html
All models haven't on-boarded driver, but You may find other model that have it.
4. Old-generation LEDs I bought in 2015
https://www.aliexpress.com/item/32443423774.html I do not recommend it now, cause it's outdated and ineffective.
I recommend #3 to use instead #4. You can use '10W' (or higher) model on regime you wish, like 3..10W(*depending on model) changing electric current from power source (driver).
I hope this will help you.
and post remarkable results.
you've chosen a great assortment of plants. I hope my grafts turn out as good as yours
