The time honored method of when to water a houseplant is usually a finger into the soil, or the “you look like you need water “method. Technology has also provided us with the probe inserted into the soil and a indicator that indicates wet or dry. I was on the website named after a very long river in South America and came across an interesting device that measures humidity. Sold in batches of 12, the device(see picture) seemed the perfect gadget for an experiment. I purchased 12 of these meters and placed them in selected plants I am now monitoring them to see if the indications provide the necessary information in a timely manner. The reading seems to indicate the amount of moisture in the container as a function of humidity. Using that value I can determine when to water the plant. ( photo / image / picture from Jerry Sullivan's Garden ) Time will tell.... Jerry
Jerry, I am a Luddite and don't trust "modern inventions", but that sounds interesting. Awaiting you results, and reports.
OK Jerry,, I am going to be the DA here ! How will you know when all are reading at 70% ? Nothing to read soil moisture,, no probe ! Think I trust the finger test best ! Stick it in the soil,, if its dry,, water them !
As it is now Mart, i don’t stick my finger in the soil anymore as I noticed that I was compacting the soil in the pot, but I lift it to see how light or heavy the pot is. That thing that Jerry is trying is like a smaller version of the system that is used on plants in businesses over here. They contract businesses to care for their office plants.
In a “let’s see what happens” scenario I placed all twelve meters in random pots, waited and watched. Yes, the meters performed their tasks and displayed a value. If all you wanted was a “water me” indication then as the plant humidity reading approached the room relative humidity value, watering the plant would restart the process. This would satisfy many. Watering would give a value around the mid 80's. This high value depends on the relative humidity around the plant. The 'water me' value, subjective in nature, is the low 40's. If all you wanted a 5000 ft view of the project you can stop here as the rest of this and subsequent posts will probably be technical in nature. The technical aspects require more than the average gardener would accept.....but some of us are curious. Welcome to garden experimentation on the fly. If anyone wishes to comment or contribute feel free to do so. This will not happen all at once. Terms, definitions, procedures will have to be established and explained. Start here: The meters need a baseline value established in a controlled environment. Definitions: Measured humidity- while there are three primary measurements of humidity, absolute, relative and specific, for this experiment we will deal in relative humidity only, which is defined as a percentage value representing the amount of water vapor in the atmosphere or in a gas. Baseline: To be continued:
I too saw a meter at the garden shop when I was there few days age. They called in four in one. It measured soil moisture, pH, temperature, and sunlight exposure. Seemed complicated to me, like something only experienced gardeners would know how to use. So I didn't buy. But maybe I should?
I had to learn the hard way that a stick meter works best in "moist" soil. Here and outside that means the day after a rain. And I mainly just attempt a pH "direction", up or down, so I know to add lime because our soil is so acidic. Soil temp is useful in spring and fall for putting out tropicals or taking up bulbs for a winter's nap. Sunlight is so plant dependent I could not say and I can measure lumens better indoors and out with a different machine. But that moisture thing that Jerry is talking about is air moisture vs soil moisture and I just don't go there. I would need something tuneable to my weird little world. We have 90% humidity and soil that is dry and cracking in the summer. It would make me nuts.
Funny, as I too was about to buy a similar gadget from an online store over here. It's a 5 in 1 meter. I'm also getting a great deal, in combination with a miniature drip irrigation system - Which I would be able to fine-tune with the help of this meter.
Wow S-H! That five in one gadget looks really awesome! And with that drip irrigation, we can make sure that no plant is lift out. Amazing ideas shared here! Thanks @Jerry Sullivan @S-H @Dirtmechanic
I have to say. Watering by numbers. The title gained my immediate attention. I recalled that in the past, many 'budding artists' endulged themselves in filling in, or adding colours to printed pictures. Surely this suggestion must have a different meaning to, watering plants. I now wonder just why this subject has become something of a scientific study or some sort of market survey on gadgets and gizmos. Presumeably the watering applies here to pot plants. Forgive me, but I shy away from the term.'House Plants'. Sorry. Just me. IMO. No such botanical specis genera as, House Plant. So. Had the question been. When should a potted plant be watered? Then IMO there would be no need for this, 'watering by numbers. Please don't read my comment as in any way offensive. I enjoy and respect members comments etc.
I just eyeball the plants. It seems to work well with most of them. They tell me when they need water. But I am curious re your experiment Jerry. And I'm also glad to see you are up to your old tricks again! Where would we all be without your experiments one this website?
