Bleach kills bacteria on contact, so you don't need to wait for it to work. I suppose it leaves chlorides behind in the soil that could be somewhat harmful, but maybe one of our chemists will comment. If so, flushing with lots of water might be a good idea. (These are non-nutritive salts that contribute to salt buildup.)

The main thing about replanting after gall is to be sure there are no fresh wounds, such as pruned roots. I have replanted promptly with no treatment and suffered no recurrence, but it's a small sample.

Thanks Michael. That's precisely what I wanted to know. Referring to samplings reminds me of my stepfather. He was a scientist.

I will replant after I have flushed it out.

Have a great Thanksgiving, This will be the first time in about 35 years that I haven't cooked a HUGE meal. We are going to the Claremont for dinner. It's a grand old hotel high in the Berkeley hills with a beautiful view of the bay and bridges.

Have a great Thanksgiving,

andrea

Andreark,

House hold bleach commonly holds sodium hypochlorite, sodium chloride, sodium hydroxide, and sodium carbonate.

The nature of a base is that it uses the chemicals in the second part of its name to oxidize substances. When doing so, it will leave behind the chemical in the first part of its name, which will most likely be sodium. A good water flush will carry the ions away.

Josh

I agree about the fresh cuts. Any injury will allow the gall to get into the new rose if any is hanging around. Switching out with new soil is the the best thing you can do. Sorry you lost a rose to gall but I'm glad it was one that is still available today.

Thanks, Josh.

Thanks Kitty, Michael and Josh.

I will flush the hole very well, let it sit a bit, then fill with 'a ton' of new rose soil. The hole is 3 feet diameter and 3 feet deep.....Then I will plant my new FM.

Thanks again,

andrea

I feel that it is important to clear up a possible misconception. The active ingredient in chlorine based household bleach, sodium hypochlorite, is not a base.

Bases are not (by definition) oxidizing agents.

The definition of an oxidizing a÷gent

"a substance that tends to bring about oxidation by being reduced and gaining electrons"

The least restrictive definition of a base is the Lewis definition:

"bases are electron pair donors"

As you can see bleach is the opposite of a base. It can be thought of as an acid with the Lewis definition. For practical purposes common household (Sodium hypochlorite) based bleach is thought of mainly as an oxidizing agent.

Commercial bleach does contain a small (but chemically significant) amount of a base, sodium hydroxide ("Household bleach is, in general, a solution containing 3-8% sodium hypochlorite and 0.01-0.05% sodium hydroxide; the sodium hydroxide is used to delay the breakdown of sodium hypochlorite into sodium chloride and sodium chlorate.")

Of importance in this forum is that sodium hypochlorite based bleach reacts with nitrogen based fertilizers to give off toxic fumes so you would not want to use bleach sterilization in a closed area such as a sunroom or in a not well ventilated area in your garden.

An example:
"Bleach, fertilizer mixture sickens people at Lowe's"

"Two employees who had tried to stop the chemical reaction with kitty litter were having difficulty breathing and complained of a burning sensation on their skin. One unidentified 54-year-old employee began to vomit and was checked by rescue workers but refused treatment, Folz said.

Fire Chief Larry Hess said the spill released chlorine gas from the bleach and 31 people, mostly employees, were evaluated. Ten people were treated for symptoms such as watery or burning eyes, but no one was hospitalized. After about 40 minutes of ventilation, employees were allowed back inside the store."

http://blog.nola.com/tpnorthshore/2007/07/bleach_fertilizer_mixture_sick.html

Here is a link that might be useful: cleaning-and-disinfecting-greenhouse link

Henry, sodium hypochlorite (the primary component in bleach) is indeed a base in water solutions. The hypochlorite ion can act as an oxidizing agent or a reducing agent, depending on what it's combined with. Combining it with an acid will release chlorine gas (toxic), and combining it with nitrogen compounds like ammonia will release chloramines (toxic). But putting a bit of it in the soil as a drench is not going to produce the toxic results you mention. Not like someone who combines bleach and ammonia, or bleach and a cleaning product containing acid, in their toilet bowl or sink. Or when a concentrated spill occurs. Someone using a 10% dilution of commercial bleach (which is already only 6-9% sodium hypochlorite) as a drench in soil would not produce toxic results in any measurable amounts, even if they'd recently fertilized with a fertilizer containing nitrogen. I've been a chemistry teacher for 27 years, and gardening for 42 years.

susan9santabarbara, your statement that it can be either an oxidizing agent or reducing agent depending on what it is combined with is correct theoretically; however practically, in water solution, it will be an oxidizing agent with normal naturally occuring household type compounds.

Concerning whether the pure compound in water is a base. It can slowly decompose to form a base. Any normal acid after reacting will yield a base as a product. (water decomposition is a reaction).

I debated using the accident report link as chlorine gas is not formed from fertilizer reactions (the police chief was wrong). However, that is an example that dangerous gases were given off.

My statement was: "Of importance in this forum is that sodium hypochlorite based bleach reacts with nitrogen based fertilizers to give off toxic fumes so you would not want to use bleach sterilization in a closed area such as a sunroom or in a not well ventilated area in your garden."

I then gave a link to a University article concerning use in greenhouses which states: " Bleach should be used in a well-ventilated area."

My chemical warnings to the public are tilted towards the conservative side as I recognize that people differ in their response to chemicals. What may simply be an inconvience to some/many/most may cause very severe reactions to a few.

The link below is to a Google Scholar search with the key words bleach lung problems ammonia

Here is a link that might be useful: keywords bleach lung problems ammonia

This post was edited by henry_kuska on Sat, Nov 30, 13 at 3:21

Henry, sodium hypochlorite is a base the moment it is dissolved in water. It doesn't "slowly decompose" to form a base; the hypochlorite ion immediately reacts with the water (it's called hydrolysis) to produce a basic solution. And with an oxidation state of +1 on the chlorine, the hypochlorite ion isn't "theoretically" an oxidizing agent or reducing agent depending on what it's combined with... it is in fact both. I do reactions in my lab all of the time which show that, and you could do that with common household chemicals as well. Chlorine has several oxidation states both above and below +1, so it's quite easy for it to go either way.

The reason I posted my original reply was to point out that sometimes it's better to actually know stuff.

susan9santabarbara, apparently I should of documented my statements.

"When dissolved in water it will slowly decompose, releasing chlorine, oxygen and sodium and hydroxide ions.

4 NaClO + 2 H2O â 4 Na+ + 4 OHâ + 2 Cl2 + O2

The above is from: http://en.wikipedia.org/wiki/Sodium_hypochlorite
----------------------------------------------
Now the word "slowly" is a relative term. Your use of the word "hydrolysis" is just another word for my (water decomposition is a reaction) statement: " Water is reacting with the NaClO to decompose (break apart the NaClO).
One can calculate the:
% hydrolysis = 0.17%
Go to the section starting: "The percent hydrolysis for the hypochlorite ion may be represented as:"
in the link below: http://www.austincc.edu/dlyon/gen_chem_1_summer04/Chapter%2018b%20acid%20base%20equilibrium%20sp08.pdf

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

As I originally stated, in commercial bleach NaOH is added to slow down the decomposition. In the above equation, adding more of a product drives the reaction to the left.

-----------------------------------------
Concerning my statement that "practically, in water solution, it will be an oxidizing agent with normal naturally occuring household type compounds.". Which you apparently feel is not sufficiently accurate for the present{{gwi:807}} discussion. Perhaps you can give us some examples of "normal naturally occuring household type compounds." where contact with household bleach would result in the household bleach acting as a reducing agent.

Here is a link that might be useful: calculation of hydrolysis

This post was edited by henry_kuska on Sun, Dec 1, 13 at 1:42

H.Kuska comment: I hope the following explanation is sufficient as to why I feel that I can safely make the statement:

"practically, in water solution, it will be an oxidizing agent with normal naturally occuring household type compounds."

"As an oxidizing agent [edit] Hypochlorite is the strongest oxidizing agent of the chlorine oxyanions. This can be seen by comparing the standard half cell potentials across the series; "

The above quote taken from:
http://en.wikipedia.org/wiki/Hypochlorite

Acidic reaction
H+ + HOCl + eâ â ýCl2(g) + H2O
Eð (V) +1.63

Neutral/basic reaction
ClOâ + H2O + 2eâ â Clâ + 2OHâÂÂ
Eð (V) +0.89 "

H. Kuska comment: The standard half cell electrode potentials are utilized to predict (a first approximation) in which direction two half reactions will go ( the half reaction with the more positive or less negative Eð (V) will go from left to right - will act as an oxidizing agent while the half reaction that is less positive or more negative will go from right to left - will act as the reducing agent.

Thus, in the table given at the following link, the neutral/basic ClO- half reaction is predicted (first approximation) to go to the right when combined with half reactions less positive than +0.89 volts (we are only interested in other half reactions in neutral/basic water solution, i.e. the presence of the symbol aq or H2O but no H+ on the left).

This Table will also give you an idea of the type of chemicals that can force Hypochlorite to be a reducing agent in neutral/ basic solution.

http://en.wikipedia.org/wiki/Standard_electrode_potential_(data_page)

Here is a link that might be useful: table of electrode potentials