The Care and Maintenance is similar with Hoya Carnosa.
This one I find somehow a bit more hardy and stable compared to Hoya Carnosa - perhaps because I had purchased them with roots in a stable pot and therefore nothing much is required except watering and feeding.
One of the best features of the plant is the heart-shaped foliage which I often noticed sold in nurseries as a Sweetheart Valentine Plant - A singular rooted leaf with love notes written on them does bring romantic mood to lovers but I must say for that particular leafy plant - it will not grow, it will remain as a rooted leaf and may survive for many months until the leaf matures and dies off.
Unless there is a stem attached to it, no new growth will appear from it.
Thus it is important to get cuttings with few nodes to ensure successful growth or the whole cutting will fail to take root and grow.
Unlike other Hoya, Hoya Kerri is a slow growing plant - thus it may take more maintenance and care to feed it often to ensure good steady growth or else it will remain as it is for many months.
This one loves sun - too shaded may cause root or stem rot and it would be too late to safe the plant.
Hoya Kerrii can be considered a stable and easy growing plant once it had found a well stable place for it to grow - ideally in a bright shaded where it is airy and well balanced humidity.
Basic Care & Maintenance of Hoya Kerrii
This require a fast draining medium - something like orchid medium mix. It does well with a mixture of perlite, sphagnum moss, cocopeat & bark mix. It should not be a strong drainage mix where it doesn't hold any moisture at all but it should not be holding water too where the roots and stem can rot too. The balance of both is ideal.
I water daily and twice during the hot dry days. They can go without water for few days to a week and perhaps you have to take note on how the foliage appearance - if it appears withered than watering is mandatory. The downside of watering will cost the leaves to turn yellow and start rotting - therefore - the right balance is necessary.
Hoya is not a totally shade loving plant but you can place them in bright indoors area. I for one had experience where when it is placed in dark areas - they rarely bloom and the growth appears to be very leggy (the leaves nodes along the stem appear to phase out far apart and it is very unsightly especially when you prefer to have a compact foliage plants)
Another thing about Hoya is they only bloom when they receive good sun. Without it - it may not bloom.
Hoya is a trailing plant and more on the wild side. The seemed to do well in most unforgiving conditions but at times - just barely surviving and it is indeed a slow growing plant - so don't expect much if you received a small cuttings and looking forward for new growth - It may take many months to actually notice anything.
I for one, just place them in their ideal spot and consider that done there and routinely water them on daily basis and weekly spray flowering fertilizer on them hoping them to bloom. Otherwise, it's another trailing green foliage plant that I'm contented with.
1) Do not dead-head the dried flower buds as the new flowers blooms from the previous dried flower spike.
2) Do take effort to foliar fertilizer on them to induce new growth or else it will remain in that same size for months.
3) It's a trailing plant - so do allow space for it to grow and trail heavy, it will climb and vine everywhere - so do take note on that garden space in place them permanently as once it captured and coiled within the garden space - it will be difficult to remove them without cause damage to the vine or foliage.
4) This plant does produce aerial roots and may start off new shoots hence a new plant from a different location where it had rooted.