JUST TESTING: A soil test is quick and simple and can tell you a lot
It has been hard to focus on gardening lately with all the shocking reports coming from the Christchurch earthquake, which came so quickly after the floods in Queensland and Victoria and the fires and floods in Western Australia.There will be much we can do to help support and encourage everyone affected by these events.I feel very grateful and blessed to live in such relative safety and comfort in our wonderful community.There's not a lot you can do sitting in front of the TV so when you need a break pop out into your garden and check the soil. As autumn approaches it is the perfect time to start improving your health and your soil's health too.Look under the plants, scrape back the mulch and have a look at your soil. The soil in your garden supports everything that grows. With all the rain we've had this year many nutrients have been washed out and perhaps there's been some water logging. If your soil is out of balance it can lead to fungal problems and a myriad of other issues. This year in particular we have experienced loads of fungal problems many of which can be traced back to the soil. The first thing to do after having a good look at the plants is to test the soil. A pH test is simple to perform but can reveal a lot about conditions the plants are enduring. Soil pH tests show how acidic or alkaline your soil is. pH means the "potential of Hydrogen" which is a measure of the number of H+ ions in the water in the soil.It is a logarithmic scale that goes from zero to 14 with zero being most acidic, seven being neutral and 14 being most alkaline. Because it is a logarithmic scale each number is really a 10-fold increase on the previous so a soil with a pH of five is 10 times more acidic than one with a pH of six and a 100 times more acidic than one with a pH of seven. However, with these tests, all you need do is look at the colours to see how acidic your soil has become. Testing in a garden recently showed the soil was strongly acidic with a pH of four to five. The problem with this low pH is that it renders most of the nutrients in the soil inaccessible to the plants' roots. Most plants will grow happily in soil with a pH of six to seven. Camellias and rhododendrons prefer medium acid soils of 5.5 to six but the soil in question was really testing them. When pH gets outside the normal range the nitrogen, phosphorus, potassium, sulphur, calcium, magnesium and many other elements plants need to sustain themselves just can't be used even though they are present in the soil. A really interesting fact is that many fungi that attack plants prefer these acid conditions. So plants in this situation don't grow strongly because they can't get nutrients from the soil so they become stressed. When they are stressed they are more susceptible to fungal attack and the fungus is more prevalent. There are several factors which lead to acidification of soils. Over watering and over use of mineral fertiliser are two of the main ones. To fix the problem the best thing you can do is add organic matter in the form of compost and well rotted manures. In this case poultry manure is the best choice because it is richer in calcium. Lime or dolomite is okay but can affect the soil's micro-organisms essential for soil health. At TOP hEDGE we recommend adding organic materials and manures because you get the added benefit of increasing the soil's water holding capacity which increases the sustainability of your garden.TOP TIPS
