Since most of our soil in the raised beds is from compost bags and is mixed with sand, i thought it about time to check the ph of the soil (apparently that means ‘potential of hydrogen’ – it’s the water in the soil that is measured, not the soil itself). Something i didn’t know up until last week.
I’ve previously used ph soil mixtures, where soil is put in a small testube with water and shaken. The resulting colour is then measured against a chart. I am guilty of losing the charts and measuring instructions, recently, but in the past have never been truly enamoured by the green sludge that i end up with.
I decided that i would invest in an electronic ph meter as (another!) little luxury. Sticking it into the soil, it seems the ph of most places is about 8. Neutral is 7 and the best ph for veg growing is between 6.0 and 7.5 as that is when the soil has the most nutrients available for the plants growing in it. Being ph8, the soil is Alkaline, where to grow most veg it needs to be slightly acidic.
I realised i needed to do something about lowering the ph of my soil so set about researching on the net. I new already that animal manure is slightly acidic and had added planty of that, but needed to know more. I found a lot of information on adding lime, including application rates for different soils etc, but this sadly is the method for increasing the ph of the soil. Not good. I eventually found some information about the addition of yellow sulphur to the soil. So, i popped down to Robery Youngs, the local garden centre and picked some up. I duly sprinkled it on the beds at the recommended rate, but it seems it takes about a year to work after being dug in! I would have liked a quick fix, but there doesn’t seem to be a safe one!
So, it’ll just have to be chicken pellets or something of the like next year if nothing improves. Or maybe i’ll just have another amazing crop of veg and not worry about it!
The ph meter is actually quite interesting as it also has a light meter on it (not that i can move my beds!) and a moisture meter (could be useful?!).
After applying the sulphur i spent some time looking at what ‘goodness’ the soil actually needs replacing after a year of having things grown in it.
The three main things the soil needs for good plant growth are nitrogen (good that i left the bean roots and the green manure roots in the soil to leave their nitrogen then!), potassium and phosphorus. These are sometimes known as NPK. It seems manure is good for this…rabbit being quite good (how would you collect so much?) and bat being particularly good apparently! I’ve stuck with good old fashioned horse manure. Nice and simple.
This led me on to find out about how much goodness the manure actually contains…i know it does lots of good to the actual soil structure, but what about the innards! This website http://gardening.wsu.edu/stewardship/compost/manure/manure0.htm contains some useful information. It describes manure as being like introducing thousands of tiny little sponges into the soil to hold in the moisture and make the nutrients more available. It also says that manure does contain a relatively small amount of nutrients and should not be relied upon alone as a soil improver.
This website http://www.nvsuk.org.uk/growing_show_vegetables_1/organic-matter-humus.php says that farmyard manure can be over 80% water and as a soil food, it is best ignored.
So where to get the nutrients from? I’ve decided to use a blood fish and bone mix. This has an N-P-K ratio of 6-7-6 and will be applied at the rate of 4oz per square yard before planting. It is organic, a balanced fertiliser and will release its goodness slowly, however it does need to be reapplies every 6 – 8 weeks.
There are many other organic and inorganic fertilisers available i’m sure but i think this will do the job nicely. This is getting complicated…