We all want to grow healthy plants and healthy plants are pest and disease resistant. Quite often we overlook the obvious. The difference between healthy and unhealthy plants is often the orchid potting mix and the fertilizing/pest control program.
POTTING MIX
Always buy good quality orchid bark, do not be tempted to purchase poor quality bark because it is cheap. Just because it is labelled “Orchid Mix” does not necessarily mean it is of good quality. Purchase your bark from a vendor that specialises in the growing of orchids.
Orchid plants generally respond well to being repotted in a fresh mix. Do not leave the plant in the same bark for any longer than 2 years. It will break down and turn into slush without you knowing. This will rot the root system and kill the plant. Soak your fresh mix in water with a little seaweed extract added before using it to repot your plants. If the roots have not been growing add Chlortan 720 to the water as well. Chlortan 720 is a great fungicide that kills the fungus that can affect root production.
Do not over water the plant as this will also rot the root system and kill the plant. Most orchids like to dry out between watering with a further reduction in watering during their dormant period.
FERTILSING AND PEST CONTROL
Times are changing and we can now grow healthy plants with eco friendly products while minimising the use of chemically based products. The biggest change is the use of products that contain beneficial bacteria. Mycorrhizae and other beneficial fungi penetrate the roots of most plants in nature. In mediums where organic fertilizers are used, the beneficial fungi can act to enhance nutrient uptake, and to break down (via enzymatic secretions from the fungi) organic matter into essential minerals useable by plants.
Root extender is one of the products that contain beneficial fungi. Use Root Extender when repotting, it is a natural product containing blended mycorrhiza and other beneficial live fungal spores. They encourage root development and a larger root network providing increased moisture and nutrient access to plants.
Establish a balanced fertiliser program. Always read the NPK ratio when purchasing fertilisers. Use liquid fertilisers on a weekly basis at half the strength of the manufacturer’s recommendations. All fertilisers have 3 numbers printed on their labels. For example, you might see 20-10-10 or 10-10-10. The numbers represent the percentages of nitrogen, phosphorus and potassium respectively. These three nutrients are the most prominent on the label because they are needed in larger quantity by your plants. Different growers have their own preference of fertiliser with different ratios of these nutrients. A higher nitrogen content such as Peter’s Allrounder (20-9-17) will encourage growth, only use it at the times the plant is putting up new shoots it will increase the strength of the cell walls.
The regular use of Neem is a good part of the program for growing rich, green, healthy plants that are pest and disease resistant. Registered and used overseas as a broad band insecticide. Add 5mls per litre to your fertiliser on a fortnightly basis.
If additional insect control is required use Sharp Shooter Bug and Insect products, or try Spectrum 200SC Insecticide. Both contain Imidacloprid which effectively controls scale, aphids, thrips, whitefly, sap sucking bugs, mealy bug, lace bug, mirids, hibiscus flower beetle and other pests.
SURFACTANTS
Wetting agents or surfactants lower or reduce the surface tension between two liquids. It also lowers the tension between a solid and a liquid matter. They act as emulsifiers, dispersants, detergents, and water infiltration agents. In short, soil wetting agents or surface-active agents (surfactants) help get the most benefit from the garden products you spend your hard-earned dollars on. For example, using a wetting agent can help liquid insecticide products adhere to or “wet” your plants’ foliage rather than simply beading up and dripping off.
GENERAL
Benefits from regular use of these products include rich, green, healthy appearance, healthy and vigorous growth, increased flower strength and strengthened cell walls. Strong cell walls play a key role in resisting insect and fungal attack.
Orchid leaves are one of the first places that a problem with roots will appear, the leaves are floppy or shrivelled. If you notice this, pop the orchid out of the pot and look at the roots. Look for insects, grubs etc. if the roots are dry and brittle then the plant has been under watered. If the roots are mushy then it has been over watered. By using the correct orchid mix for that particular orchid’s watering needs you can minimise these problems.