A common question I am asked is "why didn't my fruit trees fruit profusely or if they did why was the fruit misshapen?" Or "why didn't my camellias and azaleas flower as well this year?" Or even "why are all my coloured foliaged plants like crotons and dracaenas losing their colour?"
The answer is usually quite simple - Your garden just needs some TLC and maybe a little Potash!
Potassium Sulphate or Sulphate of Potash is commonly called Potash. It is an essential element necessary to the lives of all plants.
It aids in disease resistance and frost protection by strengthening the plants cell walls. It helps in seed and root development. It encourages strong new growth and helps with the formation of flower buds and fruit.
Potash can improve the quality and the colour of flowers and enhances the formation of proteins and sugars in fruit. Potash can even help plants with slender stems and large flower heads such as Iceland poppies and gerberas hold their heads erect.
Potash defective cues can be seen in a number of ways in your plant. Your plants might be showing signs of overall weakness especially in its stem. It could have yellowing leaf margins and grow more slowly. It could also be disease prone and its fruit and flowers will be small and poorly coloured and sometimes tasteless.
Don't confuse a potash deficiency though with an unhealthy plant. Always make sure you have given your plant some complete slow release organic fertiliser like Organic Link and a Bio Trace first.
Complete fertilisers, whether they are chemical or organic, usually contain potash. Organic Link contains potash. An N:P:K ratio can usually be found on the fertiliser label. A very quick explanation of the N:P:K ratio is - N stands for Nitrogen (greening, growing), P Phosphorus (roots) and K Potassium (fruiting, flowering).
If you use mainly a manure based fertiliser like blood and bone or chicken manure you will need to add potash as these products don’t naturally contain it.
Potash also is available by itself in a liquid form and a granular form.
The liquid form is added to water and used as a foliar spray. Used like this it is quick acting but not long lasting and needs to be repeated on a fortnightly basis. This is best for promoting flowers especially on annuals. I use Plant of Health's Potash and Silica.
The granular form is added to the soil and watered in. The granular is slower acting but lasts a lot longer. This is best for correcting deficiencies, promoting fruit and stimulating coloured foliage. We use Searles' Potash.
This weekend I want you all to get some granular potash and go a little silly in your gardens.