Haworthia indoors under grow lights all year round

[Anna91]

Hello I’m just looking for some advice please.

I recently started to collecting Haworthia this year in March.

My current set up is a shelving unit with T5 2ft x 4 bulbs
Electronic Ballast: 220V-240V voltage high power factor
Supplied with high output 24w tubes (6500K blue spectrum)
(I’ve copied and pasted that from the description of the lights I bought) I have no understanding when it come to lights

My potting mix is made up of Pumice, Akadama, Lava Rock, Grit & a small amount of soil.

I currently have the grow lights on from anywhere between 8-15 hours a day. It’s really depends when I remember or when I wake up as they are not set on a timer. I also have a little desk fan that is clipped to the shelves which is on for the same amount of time.

I’ve been pretty bad at watering them and have been doing so maybe once every 4-6 weeks the whole year. I’ve noticed a lot of them seem very thirsty and deflated. ( I’ve been super paranoid about over watering)

The main questions I have are:
Does my set up seem okay or are there some changes I need to be making?
I believe I have been under watering them so what would the recommend amount be for different times of year etc?
Now we are approaching winter should I be changing the amount of time the lights should be on?
Should I be keeping them at a certain temperature as I have no idea how much heat the lights are giving off.
This may sound like a silly question but if they are constantly under grow lights all year round does the plant know what season we are in?

I have tried to read as much information as possible but most of what I have read seems to apply more to Haworthias in greenhouses unless this Information is the same for when growing indoors
Any other advice would be greatly appreciated, I really want to try and do what’s best for them with the little knowledge I have.

I think I have around 70 of them ( will count them tomorrow) I got a bit carried away at the beginning I have only lost one so far which I think was lost to rot but I can’t be entirely sure. That’s why I ended up scared to water them.

Sorry for the lengthy post

Thank you

[esp]

It sounds like you have a good initial setup.
A simple timer for less than £5 would make management easier. Changing the "day length" on the timer will introduce some seasonality - maybe 9 hours in mid winter varying to 14 hours in mid summer. Or maybe it's not necessary for these plants - 12 or 14 hours permanently? Your house temperatures may or may not be in synch with this lighting seasonality - I'd guess it's not worth adding more heating (or cooling!) for Haworthias.
Many growers will insist that Haworthias are largely winter growers (or spring/autumn growers). Others will say they are summer growers. I've not found it to be a problem with my limited collection - I give little or no water if it's baking hot or very cold, otherwise moderate amounts. Maybe it depends on cultivation - a very warm, bright greenhouse may induce summer dormancy in a way that a cooler indoor space may not.
I suspect for many species, if they are only moderately warm, have a decent amount of light and water and nutrients, they will grow year round.
You have identified a possible problem, that you are underwatering. Rather than giving a watering timetable, the general advice with succulents is to wait until they are "dry" before watering again. Experience will gradually give you a feel for how dry to let the plants become, and how much water to give.

I'm sure there would be plenty of us on the forum who'd be keen to see photos!

[Stuart]

Years ago, when Dartford Branch used to have a show, there was an exhibitor each year who grew perfect plants of various succulent genera all in his loft with lighting so it's clearly possible. The problem as you point out is that very little is written about growing under lights. At the Haworthia Society Convention, one of the speakers obtained his equipment from shops for indoor cannabis growers which is the main market for equipment and info for growing under lights.
The things to get right are watering, feeding and heating. In the greenhouse the growing periods are easy because most Haworthias don't grow when too hot or too cold so the watering is reduced or stopped in mid-summer and the coldest winter months. Indoors, it probably won't be as cold as in the greenhouse in the winter or as hot in the summer. Watering, and feeding have to fit in with the growing periods and there's no fertiliser in pumice and grit etc. Whilst I can see the problems, I've no suggestions for the answers - sorry! It's going to be a bit of trial and error along with some help from this forum. There's no rule that you need to copy Haworthia habitat conditions or greenhouse conditions though a winter break is probably needed. Even the large European commercial growers give their plants a winter rest. Keep trying, it will work if you get bit right and you don't need to go out to a cold wet greenhouse like the rest of us.

Stuart

[Anna91]

Great!

Thank you both for your advice.

I will defiantly look in to getting a timer, The temperature of my flat will defiantly get colder over winter especially at night as i won’t have any heating on so will be interesting to see if that does make a difference.

Thanks again I will take some pictures soon, I’m just in the process of relabelling them so they all have the same coloured label.

I may have a few which I might need help identifying as well

Thank you

[Terry S.]

I can't comment on the light set-up, but a timer with 12 hours on, 12 hours off, would seem sensible. Stuart's comments are spot-on and given the relatively constant nature of temperatures in an apartment compared to a greenhouse, I suspect that haworthias would grow right through the year. A gasteria with similar cultivation need grows right through the year on our north-facing windowsill. I don't think that haworthias have any built-in requirement for a dormancy in winter or summer in the way that many mesembs do, they just stop growing when too hot.

Such purely mineral soil mixes tend to dry out really quickly and I think you need to water much more frequently. Try weighing an average size potted plant each day after watering and see how long it takes to dry out fully. That is then a guide to frequency of watering. Also following on from Stuart's comments, I think you need to use liquid fertilizer in probably every second watering. My favoured one would be Chempak 8 at maybe a quarter of the recommended concentration.

[HaoBao]

I have got about 40 haworthia in my collection and they have been inside the house for 2-3 years. I have had them on a North facing windowsill, South windowsill, under strong lights, and weak lights. I've kept moving them trying to find a good spot.

Since probably December 2020 I have had the haworthia on a shelf with two 6500K LED integrated tube lights. 4ft long, 35W each. Size of the shelf is 1,200mm x 450mm. Not really sure how the Wattage compares to yours or how the beam of light might be different so it's hard to compare. For instance my lights don't have any reflectors yet so a lot of light spills out the side. My lights are about 200mm to the top of the haworthia pots.

I have started to notice some changes with some plants. Quite a few were already stretched when they went on to this new shelf because I moved house recently and all my plants got a bit neglected. The changes I have noticed are on the haworthia Silver Swirl, the leaves are more upright now, and the haworthia Suisho is showing a bit of colour. Nothing is turning brown and the stretching seems to have stopped so I think the setup is ok.

So I'd ask if you have noticed if yours stretch under the lights or if they turn brown? If no then I think you're ok to just keep doing what your doing and water them a bit more. If you haven't been watering them enough I guess they are more susceptible to go brown since they have less water in them. If you have a fan then it should be ok to water more. I don't change the night and day period, it's usually 12-14 hours of light all year, and most of them still flower.

I think if they do happen to get a bit frazzled by the lights then maybe they can lose their roots so there's a chance of rot. If you water and they don't respond then there may be dead roots on the bottom of the plant.

[HaoBao]

The haworthia shelf

[Terry S.]

They look good and not very different to the ones in my greenhouse at this time of year.

Please note that I actually want my haworthias to show colour during the summer, "browning" is a good feature not a bad one. Root loss is usually indicated by some shrivelling and excessive loss of outer leaves.

[Pattock]

Please note that I actually want my haworthias to show colour during the summer, "browning" is a good feature not a bad one.

If it is desirable, perhaps refer to it as "bronzing"?