Suggestion: don't put sand on to of the potting mix. It doesn't do much in terms of preventing fungus gnats (which honestly are not that big a deal-a systemic insecticide will keep them at bay for 3-6 months at a time), and over time, the sand particles, being smaller in size than the soil/perlite particles, will rinse to the bottom of the pot, causing compaction and drainage issues.

As for your potting mix: what are you using? Soil is inappropriate for hoyas, which require a well-draining, well-areated mix. Some people will root their hoyas in a soil-perlite mix, and then repot in a suitable mix. Hoyas are epiphytes, meaning in nature, they grow up trees (or even in them), using aerial roots to attach to the trunks and branches. A well-draining, well aerated mix is crucial to their health. A good mix would be something like a fine grade orchid mix. Some people will add a bit of potting soil to their mix. I don't, because soil particles, being smaller than the bark and perlite, rinse down to the bottom of the pot, causing compaction and drainage issues.

You should be top watering your hoya for two reasons:

1. Feeder roots are closest to the surface of the potting mix

2. Bottom watering, especially in a soil mix, acts just like soil compacting in a pot. Since you are using a soil mix, AND using sand on top of the mix, there is already little aeration in the pot to begin with. Adding the water at the bottom, you block the only way your plant receives aeration: the drainage holes.

That being said, I am pretty sure that what I just said could confuse those who grow semi-hydro. When you grow semi-hydro, yes, there is water in the reservoir at all times. But, you are using clay balls or growstones, in which each individual clay ball or growstone is roughly the same size. This allows for tiny gaps in the pot, which allow aeration for the roots.

As for fertilization; all plants require fertilizer...even cacti and succulents. It is their "food". You should fertilize your hoya at every feeding with 1/4 strength fertilizer. I use MiracleGro water soluble tomato feed (1/4 tsp per gallon of water)-it's cheap and has all the macro and micronutrients. Most hoyas grow in rainforests of the tropic Indo-Pacific, and as such, they are constantly fed minute amounts of micro and macronutrients from organic decomposition and animal waste. We cannot replicate those conditions very well outside of nature, so a good compromise is to feed weakly weekly (most hoyas do fine with a weekly watering/feeding IF they are in a well-draining, aerated potting mix).

Aurora, thank you very much for your detailed response! Though I haven't yet spent much time on this forum, it is evident from what I have looked through that you are a very skilled hoya grower. Your collection is amazing!

I would have never guessed that bottom watering will cause increased compaction; in fact I would have thought top watering would be more likely to cause compaction. I'm glad you mentioned it.

For the soil, I used a fast draining succulent mix and perlite. Interestingly, my mother has had this beautiful hoya for probably 15 years and has only ever used standard potting soil! I will definitely keep the orchid mix in mind if the plant shows any stress in its current medium.

Do you think H. carnosa is the correct ID?

Wow, tomato fertilizer? Wonderful, I already have some of that! Thanks again for the advice!

Looks like a carnosa of some sort to me :)

It looks like a healthy carnosa to me....also, if it helps, think bromeliad/orchid when caring for your hoya rather than cactus/succulent....

Those leaves are carnosa :). My carnosa, nicknamed "Nikki", has the same exact leaves. Also one other thing: Hoyas like small pots and seem to grow and bloom better when the roots are a little snug in the pot. Trying this with some carnosa cuttings I got last week in the mail that have peduncles on them. Congrats on the new growth. Here is Nikki all untangled from her hanger earlier this spring. I've had her about 7-8 years now (the oldest cutting in there I got 8 years ago this May). She hasn't bloomed yet.

Brad AKA Moonwolf

Wow Brad! Nikki is beautiful and very healthy looking....I'm surprised she has never bloomed for you...have you tried more sunlight? Carnosas can take a lot of sun, especially in the summer when they're in active growth...I've seen plants just covered in bloom with their leaves bleached yellow and pale green from the sun....

Thanks for confirming the ID, all.

Appreciate the tip Shelley! I only used the succulent soil mix because it was what I had on hand that was fast draining. Perhaps I should repot with an orchid mix. The biggest difference I can see is that there is no bark chunks in the succulent mix, though it does have a gritty texture and I added in more perlite.

Wow, your hoya is just beautiful Brad! I would be thrilled with that even without flowers... though from the pictures I have seen the carnosas do have really beautiful flowers.

She gets some mid-late afternoon sun, and has a lot of new growth :). She has developed peduncles before, but they always seem to shrivel up on me, or what I thought were peduncles was just new growth lol. Now, the cuttings I gave away to a friend a couple of years ago bloomed for her for the first time last year. Some of her leaves are a lighter green. The lower part of the plant gets more sun than the upper part, since I have her on a large macramé hanger.

Brad AKA Moonwolf

Yes I am, Shelley. I have had my Hoyas in direct light outdoors for a long period of time, and they turned yellow and got sunburned leaves. Nikki's pretty happy where she is. LOTS of new vines, although I do have to spray her for aphids (soapy water and rubbing alcohol).

Brad AKA Moonwolf

I was just going to ask how would I know if my hoya has too much sun or not enough... right now its in a south facing window and seems pretty happy.

I had a leaf on my merrilli burn not long ago and had the familiar sun scorch ugly marking on the leaf. I moved it back towards the wall of the trailer (we live in a mobile home), where it gets more shade/bright, indirect light. I have a variegated macrophylla hanging in the bright direct light and it seems to like it so far :).

Brad AKA Moonwolf