Paphiopedilum Charlesworthii not flowering

[bobloes]

Hi All,

I have had a successful year following advice received here so thanks for that. My major non success is with this Paph. It is better than it was and has put on a couple of new leaves in the last year, I have had it almost three years. But not a hint of a flower. I feed it every two weeks and water it every week during the hot season. Lots of light but no direct sunlight. It has remained inside the whole time.

I think I read somewhere to put it out in the summer - in shade and all night? Temperatures almost always in double figures. Stress it with no water? Yes you guessed it I was a hard parent!!! Any more knowledgeable suggestions?

Thanks Bob

[Fairorchids]

Watering a Paph once a week is not enough, in particular if you have it in a bark type mix. It is hotter here in NJ, but in the summer I water 2 or 3 times a week.

Paphs require 2-3 weeks with night time temps about 7-10 deg C (15F) cooler than daytime temps to initiate buds. That cooling off should be 5-6 months prior to normal blooming time, typically in late Sept.

If you summer your plants outdoors, you will automatically get that cooling off.

[bobloes]

Thanks Kim. I shall put it outside for a couple of months. I assume it should be predominantly in shade?

[Ray]

Yes, bright, indirect sunlight works well for “strap-leaf” paphs.

These critters typically live on the forest floor, with their roots spread widely in the accumulated leaf litter, so are constantly moist, but very airy.

Don’t get carried away with the fertilizer; they are relatively slow growers without much nutrient demand. If you feed every 2 weeks, 150-200 ppm N is sufficient. (Divide 32 by the %N on the fertilizer label to get the ml/L to use. That’s about the midpoint of that range, so rounding up or down for convenience is fine.)

[bobloes]

Sorry to be a pain but I am using a propietary orchid potting mix, very dry. When I repotted my Dendrobium Berry Oda and khiekis I fattened it out with some compost and they have all done very well including flowering. Would the paph benefit from that kind of mix?

Thanks again.

[Ray]

Originally Posted by bobloes

Sorry to be a pain but I am using a propietary orchid potting mix, very dry. When I repotted my Dendrobium Berry Oda and khiekis I fattened it out with some compost and they have all done very well including flowering. Would the paph benefit from that kind of mix?

Thanks again.

Personally, I avoid compost as it can fill the voids in the primary mix and suffocate the roots.

If the mix is bark-based, pre-treat it by pouring boiling-, or at least very hot water over it. Wait 15-30 minutes and repeat. That "opens it up" so it can absorb more going forward.

For already-potted plants, just run tepid water through the medium to thoroughly soak it, wait and repeat. You'll probably only need to do that once. After tat a single drench should keep it moist longer.

[bobloes]

Thanks again Ray. I shall report back in a years time - sooner if things go wrong! All the best. Bob

[estación seca]

Most people repot paphs every 1-2 years. If kept constantly moist, as most prefer, the medium breaks down more rapidly that way.

If you're regularly allowing your plant to go dry, that is likely why it's not flowering. It only takes a few wilting episodes to set them back for some time.

[bobloes]

Thanks as well Seca. Clearly it wants to live despite my efforts!

[aliceinwl]

I have one that I grow in bark in bright shade outside that I water weekly. I bring it into the garage at night when temperatures start dipping into the low 40 degrees Fahrenheit. Otherwise outside it gets highs in the low to mid 70s degrees Fahrenheit and lows in the low 50s degrees Fahrenheit. Mine gets fertilized about monthly. Most years I get two flowers.

The only time I got one flower was when it needed a repot, these are the roots:
Re-potting Paphiopedilum charlesworthii

Depending on environmental conditions sometimes weekly watering is enough, especially if they’re grown on the cool side. Water when the media starts to approach dryness under your conditions.