Phals: High Light or Low Light?

[netrizone]

Hey guys, while browsing this forum, I've concluded that there are two general opinions on the amount of light that phalaenopsis orchids need:

1. High light: there are many threads where growers are recommended to move their phals to east-facing windows to ensure they receive enough light. Additionally, many threads say that higher light induces bigger and more vigorous blooms.

2. Low light: I've also seen many comments saying that lower lighting conditions force phals to grow larger leaves to capture and photosynthesize as much light as possible. Ray has also stated that the best phals he's ever seen were grown in a very dark greenhouse.

Please correct me if these conclusions are flawed, I'm still pretty new to growing plants. I'm just trying to provide the best conditions for my orchid. :')

[estación seca]

High light and low light aren't really defined. The best flowering in research greenhouses in Taiwan and Texas has been shown to come from 1,000 foot candles of natural daylight for 10-12 hours per day. I'm not aware of similar studies with LED lights. Excess light leads to decreases in flower count and size.

This corresponds to bright shade, with no direct sunlight and definite but blurry shadows.

In northern climates like yours, winter day length is probably more important. Many people use electric lights to extend the day length to 10 hours in winter.

Have a look at a post here about growing Phals. From the left yellow menu choose Forums then Phalaenopsis - Hybrids. Read the post in the thread at the top.

[camille1585]

I wouldn't call an east facing window 'high light' as the cumulative sum of photons per day might actually be similar to a dim greenhouse which has more uniform light levels over the course of a day.

Most Phals aren't going to do as well if you give them less (north facing window) where they usually produce fewer to sometimes no blooms.

[tmoney]

oh man, this is such a tricky topic! so we are also newer growers and so our opinion is from a beginners perspective. basically we decided that everything we read online holds about 1% weight compared to our own experience. light meters are great, but when people say "grow in an east window" or "don't grow it here" etc, this only applies to their own living room or conditions, and your east window may be totally different than their east window.

so yeah, summarise to say that following guides online is a good start, but you will not learn anything from them - in fact, if you are like us, you will only get more confused. you will learn from trying your plants in different spots for awhile and deciding where they grow best. or in other words, experience is the best teacher

[Roberta]

Speaking only from my own experience, early in my "orchid career" when my "greenhouse" was the spare bedroom. It faced east, good direct morning light for about 4 hours, then the sun shifted and light was very indirect. I got hardly any reblooming on my Phals. I got some (very cheap)shop lights (full spectrum, daylight bulbs), put them on a timer 12 hours a day, and got about 80% reblooming. Your experience may be different. But consider this approach... they did not get a lot of intensity, but rather longer duration of light, and it worked for me.

[Ray]

Many phalaenopsis species are deep understory plants that are more of less in constant shade.

The best-blooming phalaenopsis I’ve ever seen were in a hot (40C), greenhouse with saturated humidity. The algae layer on the glazing was so thick that there was very little light getting through at all. It took a minute or two for my eyes to adjust from the outside sunlight.

My current location, having no greenhouse, is a bit of a challenge. Being situated on the north side of an east-west barrier island facing the intracoastal waterway, most of my windows face north. For 7 months a year or so, all my plants are up against the north-facing side of the house, so they get no direct sunlight, but do have a wide open, bright sky delivering scattered light. They grow and bloom better than I have ever had them.