Gardeners Tips

Many plants grow best in what is termed ‘acid soil’ but what acid and how strong. How can we gardeners find answers to these questions so we give our plants the most appropriate soil conditions.

Measuring Soil Acidity

• Acidity in soil or solutions is measured in terms of the pH level. pH is the abbreviation for potential hydrogen the measure of its hydrogen-ion concentration.
• pH for soil varies on a numeric scale where, between 1 and 7 is very acidic to neutral and between 7 and 14 is neutral to alkaline basic or limey
• UK soils are normally the pH range of between pH 4.0 and 8.5. (4.0 is quite acidic and 8.5 very basic or alkaline).
• I aim for soil between 6.0 and 7.5 an this suits most of my plants

This scale shows pH in relation to common household liquids. 7.0 is pure distilled water.

What is the Impact of pH on Plants

• pH levels influence which plants will grow.
• pH levels determine if a plant can take up and use normal nutrients.
• An acid-loving plant in alkaline soil is likely to suffer and die.
• Below 5.5pH the availability of manganese and aluminum could become toxic to plants.
• In alkaline soils you may experience bacterial diseases eg in potatoes.

What Affects Soil Acidity

• Soil is not homogenous and you need to test soil from several areas. There are kits and measuring devices to help.
• The original underlying parent material will determine your soil pH.
• Rainfall and leaching can take soluble chemicals from the soil making it more acidic
• The application of fertilisers and organic matter can influence the pH level.
• High and regular crop harvesting can change the soil.

Changing Soils pH Acidity

• To make soil less acidic for vegetables, saxifrages and annuals for example you can add lime or pulverised chalk.
• Bone meal is a good source of calcium and with wood ash it can help raise your soil’s pH over time. It is used for soils that are only slightly acidic.
• Ericaceous plants such as most rhododendrons, heathers, camellias, acers and blueberries need acid soil.
• Peat is naturally acidic and a mulch of pine needles, peat moss, or shredded bark that will organically reduce pH levels. Otherwise ericaceous compounds are sold
• For container plants water several times with a solution of 2 tablespoons vinegar to a gallon of water

Footnote
The term Ericaceous is used for acidic soil or acid loving plants. Another way of looking at it is that Ericaceous plants are known as lime-hating or calcifuge plants. The term comes from Ericas which are generally peat loving moorland plants.

Rootgrow is an organic treatment that was originally launched to improve the vigour of roses via the roots when incorporated at planting. Rootgrow helps to improve the uptake of water and nutrients from the soil and is now more widely used. It encourages the roots to grow more quickly and also helps to prevent rose replant sickness. It is especially beneficial in poor soil but do not use with bonemeal as that inhibits growth of the fungi.
Rootgrow can be bought in most good garden centres or via amazon

Plants use hormones to influence and promote the development of their cells. Root stimulators, like rootgrow usually come packed with bacteria that can actually produce phytohormones directly into your plant. The hormones encourage much faster growth which results in bigger yields and faster harvests. Mycorrhizal fungi can now be added when planting as there is a symbiotic relationship that encourages healthy root growth.

According to some, quality rooting stimulators come with certain strains of bacteria, most notably paenibacillus, designed to enhance the Nitrogen your plant receives so it can help maximize root and plant health. This bacteria provides your roots with a steady stream of reduced nitrogen by converting N2 gas in the air into a form of nitrogen that can help your roots grow to their potential. ‘The volume of soil space controlled by tree roots is directly related to tree health’ Dr Kim Coder 2000

Hydroponics growers have had to deal with the encroachment of harmful fungi, usually when their conditions becomes too humid but there are certain strains of fungi that can actually benefit root development. When these fungi are introduced to your hydroponic system, they can break down debris and turn any undissolved nutrients into materials that your plant can actually absorb by increasing nutrient uptake, releasing Growth Hormones and promoting Beneficial Fungi, with Nitrogen, Phosphorous and Potassium.

A mixture of 5% nitrogen, 12% phosphoric acid, 3% soluable potash is highly effective as a plant starter. It stimulates early strong root formation and reduces transplant shock.

Good Roots and Bad Roots

• This shrub has evolved a root system that fits the landscape literally.
• Good large roots should be oriented both laterally and vertically to provide better root systems.
• Many plants need large roots for anchorage and fine feeder roots for water and sustenance.
• Higher quality root systems have several large main roots emerging from just below the soil surface.

Roots get low recognition by many gardeners but the science of root growth and root development is about to change all that. No longer is it good enough to dig a £5 hole for a £1 plant. More care and thought needs to go into the roots and their needs and aspirations.