Questions about resting period
 

Hello,

I have two orchids which have not flowered yet. I guess they have a different growth pattern than normal. I'd like to hear a few suggestions on what to do, as I recently lost a plant that didn't get a proper resting period.

The first is a laelia pumila which I own for a bit more than a year. It looks like there are pseudobulbs in every stage of growth, even one with a bulge that looks like a bud. (Pictures 1 & 2) It was also growth in every stage last winter but I thought it to be some kind of acclimatisation. From what I read, the plant rests in winter.

The second is a cattleya mossiae. (Picture 3) I bought it just before midsummer and it lost lots of roots because of shipping, thus it made a smaller pseudobulb. This year's pseudobulb is now making a second growth. It seems it won't be complete till winter, when the plant is supposed to be resting.

The plants are in 500ml ice cream containers, which I have plenty so that I can soak the pots in similar sized containers. My solution to fix these small plants is sewing a net on top so that plants and wood chips don't move around.

In the summer, the plants got brief morning sun followed by bright shade because of an apartment block. Starting from october till april, they get direct sun for a longer time. Summer temperatures are between 35 and 25 celcius. In winter it is between 25 and 15 celcius. I water the plants with less than half strength balanced fertiliser. (so that water is around 900μS/cm)

I always listen to the plant rather than a set timeline. If my plant is growing, I water and feed it as normal. When the growth stops and the plant rests, I do not fertilize and, if conditions are cooler, I water less to prevent the roots from rotting. I hope that helps.

In nature, Cattleya (laelia) pumila sees reduced rainfall over the winter, but I don't treat them that way in my greenhouse, and agree with Leafmite's approach.

The same is true of C. mossiae, although its natural period of reduced rain is Feb/Mar.

I suspect the issue you have with blooming your plants is light, more than anything else. Both species tend to grow under fairly bright conditions, and yours doesn't sound like it fits very well. You probably should consider supplemental lighting.

Thank you both for your feedback.

I was not able to describe the lighting condition properly; there's a balcony-like structure that shades my plants from summer sun (but not summer heat) at noon, from 10 a.m. on.

I guess these plants are quite resilient, compared to my two other larger hybrid cattleyas and a vanda nearby, all of which have signs of overexposure. Neither my c. mossiae nor l.pumila have any such sign of sunburn or yellowing. The leaf colours (pictures 2&3) are almost correct and it appears that mossiae can handle more light.

I have one more windowsill that faces directly to the south and gets unobstructed winter and summer sun; I guess that's a luxury in an urban environment :biggrin:. I have two dendrobium nobiles there which have bleached leaves as I was not quick enough to relocate them in the summer. I guess my problem is not solely a light problem but one that's about the balance between light and heat. Water might also a variable but I'm not playing with it a lot as I am afraid of rotting my plants.

I don't have instruments to measure light intensity but this weekend I'll try mobile phone apps instead to see how much lux the plants get daytime.