It has not been my experience at all that linearis is difficult, either to root or to grow. It is one of the more aggressive growers of my collection. I grow mine in coir chips and let it dry out between waterings.

I believe what makes it difficult for some people to grow is that its preferences fall on the cooler end of the spectrum, for Hoyas. I know Doug grows in Vermont, but I suspect the sun hall in which he grows many of his Hoyas must get quite toasty. Joni/SRQ also states that it is a fussy grower in FL.

Although some people do root in water, it is generally more effective to start the cuttings in the medium you intend to grow them in. Their roots develop with different characteristics depending on the environment they find themselves in, and water roots don't translate well to soil, so the plant more or less has to rebuild a whole new root system once you pot it up. When I was rooting linearis, I just stuck it right into the pot it's in now. I probably put it in an aquarium or tupperware for extra humidity, too.

I did an experiment once where I compared rooting in water to rooting in soil and although the water roots formed soonest, the cuttings planted in soil started putting out new growth much faster.

It can be tricky for some, I've known a few who've had trouble w/ it. I'm losing my last piece right now, think I've had it since last summer. I sure didn't know it likes things a bit cooler, hum. I also tried it a few yrs. ago & after a while lost that one too.

It is listed on David Liddle's chart as a plant with cool temperature tolerance. Joni has a copy of this document posted here.

I think you've mentioned that your apartment temperatures can rise pretty high in the summer, PG. I wonder if you put it in a room that tends to stay cooler or be more breezy, or humid, it would pull through. You could almost think of the summer months as its dormant period and sacrifice more idyllic light this time of the year.

Just a thought. I personally, sometimes struggle with sensitive temperate plants during the winter.

I agree with GG it is less stressful on cuttings to just root them in medium rather than water. I have not had much luck with my cuttings bouncing back when rooted in water then transferred into medium. I had a Hoya lenarias a long time ago and it did like to dry out some. I would since you already have some rooted good in water start introducing soil into the water container you have them in slowly over few weeks so eventually the whole container is medium rather than water. GG what do you think of that resolution?>

Well, personally I am lazy, so I would probably just go ahead and stick it into its destination pot now as long as it was looking firm and healthy.

Your mind really thinks outside of the box, Alavone. I like that. I'm not sure if that strategy would work or not! What I imagine might happen was that it would continue to grow 'water roots' as long as it was sitting in a slushy mixture. Then, toward the end you would have a waterlogged medium that might compromise the health of any 'soil roots' that started to grow. Hmm. I'm definitely not qualified to say what would happen. Questions like this really help you fine tune your understanding of plant behavior/structure, though!