PBS Forum

Neonic's have been banned with very few exceptions, within Europe for several years.

Quote from: David Pilling on November 15, 2024, 01:24:17 PMPropagation by seed does not transmit the virus

What virus?
At least some can be and certainly are. Simple logic and my knowledge of basic biology would suggest that any and all can be.

I've been thinking more about the uptake of trace nutrients like magnesium in potted plants and I remember reading that absorption through the roots is facilitated by neutral to lower pH levels in the water.  I have gotten out of the habit of checking my water for pH, but i used to do it regularly because my tap water is alkaline.  I then treated the water with a capful of white vinegar per gallon to bring the pH to slightly below 7.0. 

I just tested my tap water and the pH is about 8.5.  So, I will adjust the pH to a bit below 7.0 and I hope that this will help the plants absorb the fertilizer and trace nutrients better, and maybe help to resolve the yellow leaves problem in my Griffinias. 

I also purchased a packet of Epson Salts this afternoon.  An unscented 3 pound bag was about $4.00. At one tablespoon per gallon of pH adjusted water, it will last a long time.

So, I've got a few new techniques in my arsenal to try to help my plants. I'm hoping the pH adjustment will be the biggest help.  And if so, it will benefit my other plants as well.

Are any of you using any chemicals to adjust the pH of your plant water?

Quote from: CG100 on November 15, 2024, 02:07:41 PMWhat virus?
At least some can be and certainly are.

Any virus present. It is common to read that seed grown lily plants are virus free, for example this quote from the RHS lily group:

They can, of course, be raised from seed which has many benefits. Not least of these is avoiding the transmission of viral diseases.

I believed this and thought the way to a virus free lily garden would be to grow it from seed. Perhaps lily seed is more virus free than other seed.

Quoting Google AI (which is becoming more erratic by the day)

No, seed grown plants are not always virus free
A small number of plant viruses can be transmitted through infected seeds or pollen. In fact, about one-third of plant viruses are seed-transmitted.


There is an interesting paper:
Transmission through seeds: The unknown life of plant viruses

The PBS wiki says:

"With a few exceptions, the most reliable manner in which to obtain virus-free stock is by germinating ones own geophytes from seed."

It then goes on to list viruses, stating which ones are not passed on via seed.

Quote from: David Pilling on November 15, 2024, 05:02:24 PMAny virus present. It is common to read that seed grown lily plants are virus free, for example this quote from the RHS lily group:

But many viruses are carried in seeds, and given that no amateur ever knows either if a plant has virus, or if the plant does, which one...................................

You/the RHS has just picked a small section of one of many papers available online about virus transmission via seed. Even the one you quote goes into details about seed transmission.
Just one example -

TRANSMISSION OF VIRUS DISEASES BY SEED,

Hello again, Bern,
What if you would repot one of these plants into fresh substrate and stop fertilizing it? The new substrate should of course contain some nutrients. Are you re-using your substrate? I went back to your initial post and feel that you are fertilizing a lot. I use a soluble fertilizer of similar concentrations but I only apply it about three or maybe four times during the growing cycle and that for pots outdoors which are exposed to our heavy winter rains. I use the recommended concentration and repot every year, not re-using the substrate. With excellent results. Measuring the pH of the water certainly is a good idea, but can you also measure the pH of the substrate? Soluble mineral fertilizers do also influence soil pH to either acidic or alkaline depending on their composition.

Quote from: CG100 on November 16, 2024, 12:03:29 AMBut many viruses are carried in seeds

Yes, no argument from me now. I was merely pointing out that before this discussion I had a different (incorrect) point of view.

Quote from: David Pilling on November 16, 2024, 03:46:38 AMYes, no argument from me now. I was merely pointing out that before this discussion I had a different (incorrect) point of view.

Apologies - misread that/didn't read enough.

Quote from: Uli on November 16, 2024, 12:28:03 AMMeasuring the pH of the water certainly is a good idea, but can you also measure the pH of the substrate?

Quote from: Uli on November 16, 2024, 12:28:03 AMWhat if you would repot one of these plants into fresh substrate and stop fertilizing it?

Hi Uli,

I don't have a meter that will measure soil pH. But, I have so many plants in my typical soil mix that are doing well that I don't think soil pH is a problem at this time.

I think it is a good idea about repotting one plant and using a lesser frequency of fertilizing it to see if there is a difference between the two plants as time goes on.  I have several variables to work with now that I hope will correct the problem.

And that brings me to one more variable that I'd like to ask you, Carl, David, Arnold, or anyone else reading this post who would like to answer.

I remember reading that someone recommended using a dilute solution of hydrogen peroxide in the water for your plants from time to time. The benefit that was claimed was that the hydrogen peroxide "cleansed" the roots and this allowed better nutrient uptake that was good for plant growth.  Have you heard anything similar; have you ever done this with any of your plants; and if yes, what concentration of H2O2 did you use?

Thanks!

Hello Bern,

I have never used hydrogen peroxide for my plants. This idea seems odd to me. Hydrogen peroxide is a strong oxidizer. In the medical it is used to clean and disinfect, it removes organic detritus, blood and the like. Or think of bleaching hair.....
It may depend on the concentration but I would worry about causing more damage than good by using this for plants. And how to apply? Water a pot with substrate? For how long would it be active in the substrate? Or rinse bare roots? 

Quote from: CG100 on November 15, 2024, 12:14:44 PMI thought that the ancient tale about watering/spraying in bright sun had finally been abandoned, but obviously not. If it were true, plants would be laid waste after rain if the sun came out - something very common in the UK at least.

I think rainfall is basically formed from water vapor that coalesces around a bit of airborne debris until the droplet falls.  Except for the debris, it is essentially distilled water at neutral pH.  I guess it must be the debris that reacts with the water to produce things such as acid rain.  Water from the tap is generally more or less alkaline, with suspended minerals.  The alkalinity is used to prevent the leaching of metals into the water (small amounts of lead are found in plumbing fixtures).  These suspended minerals in the water can be left behind as the water evaporates from wet leaves, in some cases leaving a white crust behind (mineral salts?).  The same may occur with the roots.  I don't know if this is a possible source of damage.

There are other issues with alkaline water and plants affecting nutrient availability, detailed in an article in the Cactus & Succulent Society of America's journal by Elton Roberts & Malcolm Burleigh, titled "Ammonium Nitrogen and Acidic Water for Xerophytic Plant Growth" (2010 Volume 82 Number 4).    The interesting thing for bulb growers is their method seem to apply to most families of plants, not just cactus and succulents.  There is a subsequent article, titled "Watering Systems for Success in Growing Plants, Using Low pH and Ammonium Nitrogen" (2010 Volume 82 Number 6), detailing methods for everyone from small to large grow operations.  I found these freely available on the internet searching by the titles and author's names.

In what I think was an older article by the same authors, they state:

QuoteOur sole wish is to help people who are experiencing problems with their plants.  We feel that this may apply to all types of container culture and possibly to all horticulture in general.  The occurrence of highly alkaline water seems to be quite prevalent. For this reason we would allow and actually encourage the dissemination of this article as long as you don't misquote us or take our statements out of context.

I saw a photo somewhere showing the pH balanced watering system used by the curator of the Huntington Botanic Garden's world renowned cactus & succulent garden, so these ideas seem to be accepted at the highest levels.

Quote from: Ron on November 16, 2024, 03:45:56 PMI think rainfall is basically formed from water vapor that coalesces around a bit of airborne debris until the droplet falls.  Except for the debris, it is essentially distilled water at neutral pH. 

The old wives' tale is that the droplets act as lenses and scorch the plants - like schoolboys use (or used to use when I was one) a magnifying glass to either scorch things or set things on fire.

I would suspect that most rain is on the acid side of neutral today given that it will absorb only neutral of acidic gases from the air.

In the UK the vast majority of people will use either rain water from a butt, or tap water for watering. The legal limits for tap water pH here are 6.5 to 9.5.
The only resrevations that I have ever heard of in the UK have related to Proteacae and the various "bog plants" - Sarracenia and the likes. Both should be watered with rain water, although Proteacae cannot utilise ammoniacal nitrogen - they are usually fed with urea.
I don't recall seeing or hearing of water treament for horticultural use, just concerns over quantities.