Hi everyone, new plant mum here! I got a compacta about 3 weeks ago and it wasn't in the best condition. It had spider mites which I've treated and some fungus gnats which has appeared about 1-2 weeks ago which I'm in the middle of treating. I just noticed these black spots on the leaves today. I thought it was dirt at first but it doesn't come off when I try to scrape it. Any clues as to what it is and what I can do to treat it?!

FYI - it's been bought at a plant shop and they've stuck a sticker on the side saying its just been repotted and not to do repot till later in the year. It's currently at the end of autumn where I am.

Many thanks in advance

I'm not sure. I would keep an eye on it, and maybe remove the affected leaves; if it doesn't spread you're okay. I would also ignore that nursery sticker and repot pronto -- that rich soil mix might work in the controlled conditions of their greenhouse, but in a normal home environment, that is WAY too heavy. It won't dry fast enough and increases your risk of root rot and fungal/bacterial issues. Hoyas are epiphytic, and semi-succulent, and they need a loose and well draining mix. A common formula is half potting soil (succulent or regular) and half orchid mix.

It might be edema/oedema, which is a condition where the plant's cells basically burst from taking up too much water. A heavy soil could definitely cause that problem even if you were really careful with watering. I agree with Rose's suggestion to repot despite the sticker.

Thanks guys will definitely by repotting it

The container that your Wax Plant (Hoya carnosa 'Compacta') is growing in appears quite large for the size of the plant and the soil looks extremely wet. Hoya's require pots with really good drainage and a porous soil. I'd suggest removing the attached saucer from the pot, which can hinder air circulation. The black spots on the leaves may be a fungal issue due to the soil retaining too much water and lack of proper aeration at root level.

Fungus Gnats are usually present when soil stays too wet.
Spider Mites are usually present in dry, arid conditions with lack of air movement.

If you repot your plant, I'd suggest using a small pot that has lots of drainage holes in the bottom and use a potting medium like the one Rose suggested. I've been using a mixture of potting soil combined with lots of perlite and orchid bark mix that was recommended to me about 15 years ago by an experienced Hoya grower.

Hoya Compacta has very pretty, fragrant blooms but I no longer grow it because it was a mealybug magnet in the humid climate here in Florida where I live and it was extremely difficult to eradicate the mealybugs from all those nooks and crannies.