Hoya bellas with yellowing leaves

[Colm Osiris]

i have four Hoya bella plants, which were all grown from cuttings. the two in the black pots were planted last October, and the two in the brown pots were planted at the beginning of this summer. there are now some yellow leaves, and the flowers don't seem to be developing properly.

they've been on a north east facing windowsill, but now it's getting colder, i've moved them. they're in the same room, but opposite the window, so about 11' away from it. and they're all facing the opposite way from what they were. the lowest the temperature got on the windowsill was 17.5℃. the shelf they're now on is about 20°. i will put a minimum/maximum thermometer on it to see what it's like overnight.

i've been using a moisture meter to help me with the watering, and i put it in two places in each pot because the spread of water is not always even. i don't think i'm overwatering them, but it's possible. thanks for reading.

i'm really hoping there's a simple explanation and solution.

 

[Anniekay]

Hoya like to dry out well between waterings because they store water in their leaves. Let them get very dry before watering and be sure that they are in well draining soil, not moisture retentive soil with peat in it.

 

[Colm Osiris]

thanks for that. they were on the windowsill, and were taking up quite a lot of water, but as the weather has got colder, i may have been watering them too much for too long.

these plants were all cuttings from another plant, which died last winter, starting off with yellowing leaves and i want to make sure that doesn't happen to these. i've moved them now, they're on a bookcase about 11 feet from the main window.

no, there's no peat in the soil, it was 50% organic compost, 25% perlite, and 25% orchid bark.

i have a moisture meter, but i'm not sure how accurate it is. also, now the plants are now on a bookcase, there isn't room for it, and i'd have to move the plants to measure the moisture. i'd rather not do that. some apparently healthy leaves have dropped, so i don't want to do anything to encourage any more of that.

so, utter noobie question, how do i tell how dry they are? presumably it's how wet the soil is at the bottom that counts? is there any kind of calculation i can do, to do with temperature and light maybe?

 

[Anniekay]

How you tell is stick your finger in the dirt down to about 3/4" , if That's dry then you can water them. They're turning yellow and dropping leaves because of way too much watering. Thick, fleshy leaved plants store their water in their leaves, like camels store water in their hump, they do not need to be kept wet and will rot if you don't let them dry out.

 

[KarenandEli]

Oh dear oh dear....my mother got a cutting from the next door neighbor in 1966, it bloomed that year so it was 7 years old...the plant is as old as I am. It was always in the east window of the kitchen, nice humidity since we always cooked. I'm no botanist, no expert... but this plant has moved with me and survived for 65 years. Once every 5 years I change the soil. Miracle grow soil. I water it when I remember, I don't fuss with the soil...It drops leaves sometimes, but it flowers a couple times a year. The only cuttings I take are few and far between but I make sure I involve a flower bud so that whoever I give it to gets a flower the next year. Do I talk to it? yep. I guess after 65 years, it's one of my closest friends. It is still in the kitchen. Facing east.

 

[KarenandEli]

Oh dear oh dear....my mother got a cutting from the next door neighbor in 1966, it bloomed that year so it was 7 years old...the plant is as old as I am. It was always in the east window of the kitchen, nice humidity since we always cooked. I'm no botanist, no expert... but this plant has moved with me and survived for 65 years. Once every 5 years I change the soil. Miracle grow soil. I water it when I remember, I don't fuss with the soil...It drops leaves sometimes, but it flowers a couple times a year. The only cuttings I take are few and far between but I make sure I involve a flower bud so that whoever I give it to gets a flower the next year. Do I talk to it? yep. I guess after 65 years, it's one of my closest friends. It is still in the kitchen. Facing east.

 

[Colm Osiris]

Oh dear oh dear...

thank you for your story, but i'm not really sure how it helps me. sorry, but i need encouragement, and "oh dear oh dear" doesn't feel at all encouraging.

 

[Colm Osiris]

How you tell is stick your finger in the dirt down to about 3/4" , if That's dry then you can water them. They're turning yellow and dropping leaves because of way too much watering. Thick, fleshy leaved plants store their water in their leaves, like camels store water in their hump, they do not need to be kept wet and will rot if you don't let them dry out.

thanks. i've only watered them once since i moved them. hopefully they'll be ok now. while they're on shelves, i can water them from the bottom, but when i put them in hanging baskets, which is the plan, i'll only be able to water them from the top. does it matter?

 

[Colm Osiris]

now what's happening is the plants are losing healthy green leaves. not many, but still some. could i now be underwatering them? the temperature in this room varies between 16 at night and 20℃ in the day time. it is quite damp here, but i have a dehumidifier working all day. i also have an air purifier, which does give out a bit of cold air, but it's the other side of the room from the Hoyas. i really want to get this right, as these plants are very special to me.

 

[Anniekay]

Plants enjoy humidity and lack of it will dry the leaves. Turn the dehumidifier off is my recommendation. Doesn't matter if you water from top or bottom just water the soil and let them dry between watering.

 

[Colm Osiris]

thanks. yes, they do, but Hoya bella leaves are slightly succulent, so doesn't that mean they can afford to be a bit drier than "normal" plants (whatever they are!)? i've turned off the dehumidifier for now, at least. i've also ordered a professional humidity/temperature meter, which i hope will help. i don't think the one i have is very accurate. but the damp leads to black mould, which won't do me or the plants any good. so i have to find a happy medium.

the soil in the pots is quite low now. should i top it up?

as i moved the plants from the windowsill, a very small piece fell off. it was only three pairs of leaves, and too small for a jar, so i made a hole in a piece of greaseproof paper over a little jar, and it is growing roots. so, as one of the more recently planted of the plants is not going to make it, i've taken off the green end of the last remaining stem, and i'm going to try the same. it's a bit bigger. so hopefully the three remaining plants will soon be joined by two new ones.

the two older plants are definitely coping better than the two newer ones.

the thing is, i seem to be quite at potting up the Hoyas, but not so good at keeping them alive. and this needs to change. i need to make sure these plants survive healthily through the winter, as well as the cuttings.

would hanging baskets be good?

 

[Anniekay]

Mine are in hanging baskets but I don't think that matters.

They store water taken up from the soil, so they need the soil to dry out but,...the Air needs to still be humid enough to keep the leaf tips from drying out. They are still tropical and not desert plants. Desert plants don't mind low humidity, tropicals need humidity.

 

[Colm Osiris]

got it. thank you. would they benefit from misting, then?

 

[Anniekay]

got it. thank you. would they benefit from misting, then?

No, don't obsess, just normal humidity.

 

[Colm Osiris]

thanks. i'll try not to!