Beginner with a few sh questions
 

I just completed the design and build of an indoor grow chamber for my poor orchids that have endured low humidity, low light and low temperatures for several years. The grow chamber seems to be doing well so far, keeping temp and humidity in acceptable ranges with no temp or humidity controllers. I am converting my 6 orchids to sh using the dual pot method with water gauge.

I am using distilled water and Solo-e only. The directions on the Solo-e say to "Use at a rate of one tablespoon per gallon of water every two weeks, using plain water in-between"

So here is how I have implemented:

- Water with distilled/solo-e as needed for 2 weeks.
- Water with only distilled water for 2 weeks
- flush with tap water
- Repeat

I might add that I am NOT emptying the remaining water when I switch to only distilled.

My Q's:

1. Does that regimen seem correct?

2. Will tap water work OK for flushing? I don't know the TDS of my tap water, but would assume it is like most other municipal water supplies.

Thanks,

Joe

Hi Joe,

Be sure you read the large amount of S/H information on the Web site of the guy who invented it:

First Rays Semi-Hydroponics

Most people who grow in S/H use a very low concentration of fertilizer at every watering, with an occasional flush of pure water. I am having great success with this method.

I use Michigan State University (MSU) blend for pure water, 13-3-15 at 1/8 teaspoon / 0.625ml powder per gallon / 3.78 liter of rain water. This gives about 20 parts per million of nitrogen (ppm.)

I flush with rain or reverse osmosis water about once a month.

I'm not familiar with your fertilizer, but it has numbers on the label. You can figure out how much of your stuff to add to a gallon to get to your desired nitrogen concentration. Hint: A lot of S/H growers use around 20-40 ppm nitrogen.

There is also a fertilizer calculator on the First Rays Web site:

here.

2. Your water utility publishes their water report annually. You can find it online. You can read the TDS in your water. It varies dramatically across the US so you need to find out, and not hope.

Most orchids do well with 200 ppm or less, including the fertilizer. Phrags and a lot of cloud forest orchids should have much less than 200 ppm TDS. People in much of the eastern US can use tap water for orchids with no problem. Mine varies from 850-1200 ppm so I collect rain.

Joe,

Your use of SOLO-e once every two weeks is fine, but not dumping the reservoir when you water might be an issue.

Starting with a fresh reservoir of nutrient-bearing water, the plant starts absorbing the nutrients, so that changes the chemistry. Add to that the fact that for every nutrient ion the plant absorbs, it must expel a compensating one, and that affects the reservoir chemistry as well. Then, as the plant's gas exchange processes go on through the root system, the solution is affected even more. And, as if that wasn't enough, as the water evaporates, all of that gets concentrated.

The plant can tolerate that "off" chemistry for a while, but by not flushing, you're making it do so for twice as long.

--------------------

E.S. - the SOLO-e is a blend of K-Lite and KelpMax at a concentration that designed to provide the equivalent of a frequent, low fertilizer dose, when applied every two weeks. No further calculation needed.

Thanks for the reply Ray.

It is easy enough to dump the reservoir before each watering, so I will do that.

Any thoughts on using tap water to flush, vs using distilled?

Also, I wasn't quite sure if you are suggesting JUST emptying before each watering, or actually flushing every 2 weeks instead of once a month.