A Gardeners Blog: Scotsburn's Environmental Disciplines

Argyranthemum Molimba Red

I was asked about our "Organic Principals" this week. "Organic" has so many complicated subtleties that I chose to avoid the term and write out for further discussion and clarification a series of "Environmental Disciplines". I'm comfortable that we live up to these disciplines, what we need to do from this point is to keep working at them and steadily remove the practices that prevent us confidently claiming to produce "Organically".

Poppy Matilda

Environmental disciplines.
We use a number of “Environmental Disciplines” to achieve our environmental aims.
Variety selection. Plants grown will be environmentally positive. Select heritage and Open Pollinated (OP) varieties where expected garden performance allows.
Clearly identify Hybrid varieties and their cultural benefits.
Avoid Genetically Modified (GMO) breeding.
Give preference to seed and stock material bred and produced locally.
Avoid environmental weeds.

Potting media. Choose media materials that are renewable and collected responsibly. Pine bark and coir are the preferred base materials. Continue to trial alternative substrates including greenwaste as they become available.
Pre-blended pesticides are not to be used.
Fertilizer practice balances the conflicting needs of retail and consumer longevity with environmental sustainability. Continue trialling organically based materials such as hoof & horn.
Maintain low Phosphorus levels to help manage plant stretch.

Supplementary fertilizers. Liquid fertilizer is used to maintain vigour and tone plants for retail display. Balancing pre-blended fertilizer levels with liquid fertilizer applications helps reduce fertilizer run off. Current liquid fertilizer best practice is chemically based; continue to look for environmentally sustainable alternatives.
Maintain low Phosphorus levels to help manage plant stretch.
Plastics. Plastic containers and labels are washed and reused wherever possible. Plastics no longer usable are collected, sorted and sent for regrinding and recycling.
As biodegradable and sustainably produced containers and labels become available trial and introduce them immediately.
Pesticides. Minimization of plant stress through provision of the most appropriate growing environment, media, container and water is the primary means for avoiding pest and disease infestation. Pesticides are used to target specific infestations as they arise.

Insecticides. Monitor crops and treat outbreaks as they occur. Preference is given to pesticides with low toxicity and environmental safety. Bts, Spinosad are preferred grub sprays. Oils and Clensel are preferred for sucking insect control. If control cannot be achieved effectively then systemics are applied.

Fungicides. Primary foliar fungal problems are Downey Mildew, Powdery Mildew and Alternaria. All are best managed by avoiding infestation through environment management: high light, air circulation and water management. When infection occurs Fungicides will be used as a tool to help alleviate symptoms but only as a part of a broader strategy aimed at getting the plants growing vigorously.
Root rotting. Pythium is the primary fungal concern. Nursery hygiene: potting mix storage, drainage and removal of old media; is the most effective form of control. Phsophonic acid is a safe and effective drench as plants are transplanted.

Herbicide. Herbicides are rarely used on potted plants. Pre-emergent herbicides may be used on very long term crops but we prefer to manage weeds through nursery hygiene practices and minimizing the time plants are kept in any one pot.
Knockdown and pre-emergent herbicides are an important part or our hygiene program. Between crops all gravel based growing areas are treated with herbicide. We have and will continue to trial alternatives to chemical herbicides such as Pine oil and burning but to date these have proven very costly to achieve adequate results.

Plant Growth regulators. PGR’s are disliked by most home gardeners, there is a general feeling that they are hidden and not to be trusted. We do not use PGR’s in our nursery and request that our suppliers do not use them on plants supplied to us. Plant growth is managed through pruning, container selection (appropriate pot for plant size), fertilizer program and water management.