How I Grow My Hoyas in Semi-Hydro and why?

The relationship between Hoyas and their collector is quite a personal one and differs by everyone’s unique strengths and weaknesses when it comes to the individual’s care and routines. Factor in your environment and whether or not you grow them outdoors or indoors, it’s easy to see why everyone’s growing conditions are so unique and personal.

For me personally, I have always been a helicopter plant mom, and that usually equates to the acquired skill (or lack thereof) of overwatering my plants and having the root systems die by drowning. When I first got into Hoyas, I kept every single Hoya I purchased in the same substrate that  they came to me in, back in 2020 that looked like chunky mix, usually a mixture of soil, orchid bark and perlite, since pon and Leca were not as prevalent during that time. They did ok in that mix for me, slow but consistent growth since I was not fertilizing. However one by one they all just eventually rotted and died and I couldn’t understand what I was doing wrong. By digging them up, I always discovered the roots turned mushy and stringy and they would just pull right off the Hoyas stem, at that time I did not realize that this was what root rot looked like due to overwatering.

I then discovered leca and pon and the art of semi-hydro and I was immediately intrigued and amazed at how plants can grow so big and beautiful in inorganic materials like clay and rocks?! I had so many questions, how do they survive without soil, the life source of all plants (or so I thought), what do they feed on, where are the nutrients?? 

After a copious amount of research I realized the answer; it’s all in the water. Hoyas are epiphytic plants, which means in nature they climb on rocks and trees, so when growing them indoors, leca and pon gives the Hoyas’ root systems something to cling onto and wrap around (mimicking its natural habitat) as they establish their life source for optimal growth. The nutrients that aid in that growth comes into play in the water that you use to water them with. Since leca(clay), and pon(horticultural stones) are both INORGANIC substrates, which essentially just means that they do not deteriorate over time (which also means they are reusable, go environment!), they do not have the necessary nutrients that Hoyas need to grow and bloom such as potassium, magnesium, calcium, phosphate…etc. Even when I switched to leca and pon, I did not have this information right away so my Hoyas finally stopped dying, but they were not growing. I was super frustrated because my collection stayed 1-2 leafers for a very long time (embarrassingly 2 years for a lot of them). Queue more research and I finally tackled that issue which brings me to the products I use today in my nutrient water, which are all linked in the  “Products” tab:

*It is super important to add the products in this order to prevent  nutrients lockout (nutrients canceling each other out).*

CalMag: For those that especially love to grow big leaf Hoyas, this is a must in your water. CalMag is short for calcium and magnesium, two very important chemicals that help prevent nutrient deficiency. Calcium is needed for cell wall structure, development of roots and proper nutrient transport through the entire root system. Magnesium aids in photosynthesis, chlorophyll production and enzyme function. Most fertilizer may already have these in there already but in lower amounts.

Tezula MSU Fertilizer: Now this part is pretty personal as every collector has a brand of fertilizer that they are comfortable with and potentially have been using for a long period of time. I switched to this from the GH trio most semi-hydro growers like to use mostly because it’s all those 3 steps into one. 

CleanKelp: this step is optional, if you get overwhelmed and would like to cut one thing out, this would be the product that can go without harming any potential growth. This product is essentially sea plants extracts that help regulate the roots hormones and development. I will say however, ever since I incorporated this into my routine, more Hoyas bloomed and consistently for some species. 

Diamond Nectar: this product is a humic/fulvic acid, which is needed for your plants’ root system to intake nutrients efficiently thus better absorption and distribution of all the prior nutrients you have added before this step.

Hydroguard: I cannot suggest this product enough. I believe that every single collector, (semi-hydro or not) should incorporate this product into their water. This product is a root inoculant, which means this product takes any decomposing matter that can be found within the root system and actually turn them into nutrients for the plants to eat, ie. NO MORE ROOT ROT(or less of it). 

Hopefully all that information hasn't overwhelmed you already, because there’s no gate-keeping here! I believe that every collector deserves the knowledge on how to grow their Hoyas into big and beautiful Hoya trees. And it’s also in my best interest because the better everyone grows their Hoyas, the faster it gets into circulation, which means more Hoyas for me(and everyone else I guess)!

It is also important to note that I grow all of my hoyas indoors under artificial lighting, so what works best for my growing conditions may not be what works best for you.

 FAQs

Do you fertilize with every watering? 

Yes I absolutely fertilize with every watering (every other week for self watering pots and weekly for small props), and all year round.  I had given my sister a few small Hoyas and she went without fertilizing it much because she was weary of fertilization burns. Fortunately, Hoya is a genus that can withstand heavy feeding without any detrimental effects, with the correct label usage of course. In fact I fertilize them from the very beginning as cuttings. I truly believe that if you start them out with the good juice, it will create a very strong foundational root system that will go on to make healthy cuttings for generations! 

What are your exact measurements for each of the products? 

Calmag: 5ml/gallon 

Tezula MSU: 1tsp/gallon 

Clean Kelp: 5ml/gallon

Diamond Nectar: 5ml/gallon

Hydroguard: 2ml/gallon 

These are the measurements that I have been using for a couple of years now, it is for aggressive growth so please adjust to what you feel the most comfortable with. 

Do you incorporate pest control/treatment into your water?

Yes I do. I switch between Azamax (1/8ml per gallon) and another potent systematic(please dm me through insta for this product if interested. I do not feel comfortable advertising this product as it can be very toxic to kids and pets when used as certain applications). I will be going into further details about pest treatment and prevention in another blog post! 

What are your exact household conditions?( This will soon change as I am in the process of moving so my environment will drastically change.)

Ambience: 72F with 30-45% relative humidity

Milsbo Tall: 75F with 70-80% relative humidity 

Marshydro Tent: 85F with 90-95% relative humidity