I'm not so certain about the "
does no harm" theory. This nursery did a small pot trial and found that water was actually better at treating transplant shock then Vit B. It's worthwhile reading the article, though the great thing about the internet is that you can always find something to support an argument, which is why you should do your own pot trials.
http://www.almadenvalleynursery.com/site/breaking-the-vitamin-b-1myth-articles.php
Frank,
The article above offers some suggestions. I have found the simplest method is to make up a stock solution and then dilute when required. I use an electronic kitchen scale to measure chemicals, and a simple plastic jug for liquids is sufficient. It's not difficult and the stock solution will keep as there is no N in it for grow algae. Does mean having some bags of chemicals, but, they last for ages and minimal amounts mean you only need small bags, which are usually available at larger garden/hardware stores.
Add 20g potassium sulphate (K2SO4) to 20 L of water, dissolve; then add 7g mono potassium phosphate (KH2PO4) and dissolve. To use, dilute 1 litre with 9 litres water to make 10 litres, or 1/2 litre with 4 1/2 litres of water. If you want to add magnesium add 56g Epsom salts, calcium is best added as gypsum to the pots. Use this final solution every time you water.
The rational is that K is essential for water uptake by plant roots and is essential for stomatal closing. By removing roots during repotting the capacity of a plant to take up water and regulate dehydration is impaired, by adding K to the plant, it helps to reduce water stresses.
P is required for cellular health, cellular respiration is entirely dependent on P.
Plants have a good store of N in the trunks, so they don't need N until normal plant growth resumes. Plus a plant has to expend energy in converting fertilizer N to a usable form, energy which may be better spent on pushing buds and forming new roots.
Paul
