An experiment with semi hydroponics

I have thought about experimenting with growing my plants in semi hydroponics for a while now. It’s supposed to work well with Hoyas, but I recently changed their soil and didn’t want to stress them too much, so I went with the next best thing – my Adenium arabicum. This one have always had a bit of trouble growing new feeder roots after a heavy handed repot. Maybe the new, fine roots couldn’t find their way through the fresh soil and they just decided to not grow at all. This makes it a good candidate for semi hydroponics. Apparently, even caudiciforms, like Adenium, like to grow freely in Leca and water instead of soil. Semi hydroponics is basically water therapy for plants. The roots grow straight down into a reservoir of water with nutrients and you never let it dry completely.

How I’m doing it.
The first thing I did was to clean the roots. It took a while to remove every single piece of soil and clay, even with most of the roots gone from the last repotting session, but I think I got it all in the end. If I accidentally leave a piece of dirt in there, it may end up causing root rot.
I decided to use a plastic nursery pot and a transparent glass reservoir, so I know how high the water level is inside the plastic pot. I decided to keep the water level low at first, because Leca will act as a wick and transport water to the roots. Right now I don’t know how well my setup works. I just want to avoid causing harm to the roots before they get used to growing in Leca and water instead of soil.
I decided to order a set with 3 different kinds of fertilizer, specifically made for a semi hydroponic setup. I think they’re called Micro, Grow and Bloom. Leca doesn’t have any nutrients in it, so I’ll have to carefully monitor how much to add and when to do so. All of this is basically an exciting experiment for me. I’ve never done anything like this before.

I’ll make sure to keep you updated on my new project. Maybe it will end up being a huge project with different types of plants. Or maybe it will kill my Adenium. Only time will tell.

Sulcorebutia rauschii, the purple, spineless cactus

Look how much my Sulcorebutia rauschii has grown in 2 months! This pot will be too small for it very soon. I feel like this cactus grows like weeds in a lawn.
This one is perfect for the impatient cactus lover. It seems like it grows faster than many other types of cactus (at least after they reach a certain size). Each pup grows a set of babies, which then grow another set of babies etc. Eventually you will have a giant pot of purple bulbs in your garden.
I didn’t get any flowers on my Sulcorebutia this year. Technically, it can still happen, but right now is the time to be careful about watering the outdoor cacti. I wouldn’t want these guys to rot.

Cotyledon tomentosa seedlings, 2 weeks old

I think.. more seedlings germinated. I wonder how many I actually planted. The germination rate must be crazy high if the seeds come fresh from your own plants. They don’t seem to grow very fast at all, but I like how adorable they are at the moment. At some point I probably need to weed out at least 50-70% of them depending on how big they get when they start to develop their true leaves. I don’t think I need 300 Bear Paws.

My Hoya retusa is blooming!

Hoya retusa is pretty special in many ways. It doesn’t look like your regular Hoya. I think most people would just keep walking if they saw this guy in a flower shop, wondering why they sell expensive grass – and more often than not, unlabeled, like this one was when I found it. It’s also special when it blooms. Unlike most other Hoyas, Hoya retusa doesn’t grow peduncles. Singular flower buds grow directly on the main stem and fall off when they’re done. The flowers have a very faint scent of lemony cough drops.

I’ve been watching my retusa explode with growth, lately. I have to constantly control the vines to keep them from trailing the ceiling or grabbing my other plants.

Stapelia grandiflora, 4 years old

My seed grown Stapelia grandiflora are now 4 years old. They’re massive, too. These plants grew from only 5 small seedlings and they’re now filling an entire 20 cm pot.
I’ve been keeping an eye on this flower bud for a while now. It’s not growing bigger, but it’s not yellowing and falling off, either. Stapelia can bloom several times a year, even in fall. I’m hoping that the weather will be kind on this flower bud. I really, really want to see how big and smelly the flowers are in real life.

Adenium obesum, 7 months old

My Adenium obesum seedlings are already 7 months old. I’m using my hand as a size reference. The seedlings are getting kind of big.

I’ve been leaving them alone, letting them grow as they please until next spring. If I keep pruning them in fall, there’s a chance that they won’t grow new leaves and branches immediately, because their growth slows down when the weather and room temperature gets colder.

1 week old Cotyledon tomentosa seedlings

There are so many seedlings now and more are still germinating. I have already harvested the next 10 flowers and will be keeping the seeds in a dark and dry place for the next few months. Next week I’ll have just around 600-900 seeds for if this batch fails.

I still keep them under grow lights in a bag to keep humidity up until the rest of the seeds have germinated. I don’t know exactly when you’re supposed to remove the bag and allow the seedlings to grow in lower humidity. Usually, succulents can handle lower humidity earlier than cactus seedlings, but these are just so tiny! They’re only 2 mm wide and haven’t reached their succulent stage yet. This really is a trial and error adventure.

My seed grown Lithops just turned 5!

The Lithops “seedlings” don’t get much attention on this blog anymore. Mostly because they don’t actually do anything at all. They’re slightly dehydrated after a good and warm spring and summer without any water. Right about now would be the growing season for adult Lithops. They need water before they start splitting in late fall/winter and then you stop watering again until the old leaf set is dry like a piece of paper. I keep these guys in my South facing window in the living room. So far they haven’t shown signs of etiolation.

I’m not actually sad because they’re not growing bigger or blooming. I just kept 4 seed grown Lithops alive for 5 whole years (+1 month)!