Preventing Pests and Diseases

Hygiene

The basic rules of hygiene that apply to humans also apply to plants. It’s easy to think with them growing in dirt that using dirty secateurs/snips is ok, or that dead leaves are ‘part of nature’, but clean hygienic practises will reduce the likelihood of pests and diseases. Recently leaf-miner moths have been causing problems for horse chestnuts and they are known to live and over-winter in the leaf litter at the bottom of horse chestnut trees.

Any time you are going to cut a plant, whether this is removing leaves, harvesting fruit or pruning, a clean sharp implement should be used. The cleanliness reduces the chance of infection in the ‘wound’ by bacteria or fungi and using a sharp blade reduces any chances of tearing the ‘wound’ which would reduce healing time and give a larger surface area for infection.

The removal of dead leaves (both on and off the plant) as well as any diseased or damaged parts of the plant should be standard practise (known as the three D’s). However be careful not to break out the chainsaw every time a leaf becomes slightly yellow, simply wait till over 50% of the leaf appears irreversibly damaged/dead before removing. With diseases however, once identified, remove all infected material as soon as possible. The infected material should then be burnt, or hot composted to stop any spread. This will reduce the chance for the disease to spread.

Nutrition

As a producer of plant fertilisers, it seems somewhat bias that I would say that the right plant food can prevent pests and diseases. However there is truth (and a little advertising!) in this. One of the most important things you can do to prevent the majority of pests and diseases is to have strong healthy plants. Healthy plants are much more able to use their own natural defences to resist P&D, and are likely to survive for longer compared to a weaker/sicker plant. So using a balanced fertiliser with a full range of secondary and micro-nutrients to maintain healthy plant growth is strongly recommended.

As well as general health there are a few nutrients that can help a plant to build stronger defences. Silicon (often in the form of silicic acid and Potassium Silicate, its Potassium salt) can be added to all feeding regimens to increase strength throughout the plant. Not only will this reduce the chances of stems snapping under the weight of a heavy fruit such as tomatoes, but it makes it a lot harder for sap-sucking insects (such as aphids) to penetrate the plant. Furthermore the plants become more resistant to extreme of temperature and drought. Plant Magic sell Bio-Silicon for using a soil-based mediums or with hand watering and Hydro Silicon for use in Coco and Hydroponic growing set-ups. This combines available silicon with bio-stimulants to improve the uptake of the silicon.

In nature plants often form symbiotic relationships with other organisms. A symbiotic relationship is where two organisms benefit from living together for nutrition or protection. Plant roots can be protected from soil-borne pathogens by forming a symbiotic relationship with a beneficial fungi such as Mycorrhiza. The fungi covers the roots, protecting them whilst taking carbohydrates from the root for nourishment. Plant Magic Granules are a blend of Mycorrhiza, Trichoderma (another beneficial fungi) and bio-stimulants that will help protect your plants root system.

The above ground parts of the plant can be protected from fungal spores and airborne pathogens using biofilms created by friendly bacteria and other microbes. These can both combat, and impede botrytis (black mould) and leaf spot fungus. Essence from Plant Magic has a consortium of beneficial microbes to protect a range of plant types and growing environments and contains a microbial feedstock that will allow it to thrive straight away.

Ultimately all these preventative measures are subject to observation and care of your plants. A regular inspection of your plants is key to look for signs of deficiencies, pests, diseases and to keep a check on temperatures, humidity and ventilation. The sooner a problem can be identified, the better chance there is of stopping pests and diseases from causing damage.