First - thank you for supporting small business. Whether you have bought a bottle or are just visiting our site to learn, you are helping our little family and community grow. Our products are made and bottled in rural Virginia, bringing jobs and money to the local economy.
Plant Bodyguard concentrate is a Clean Green Certified pesticide/fungicide for use on various food and non-food crops. It is made from ingredients on the EPA's "minimum risk" list, and thus is exempt from registration. Plant Bodyguard is extra concentrated with potent ingredients like thyme and peppermint oils, and less of the 'filler' ingredients our competition uses like cheap soap and vegetable oils. Side note: we now make a very high quality general liquid castile soap, available here.
The general rule is 1/4fl oz (~7ml) to 2fl oz (~60ml) per gallon of water, depending on the type of plant and/or issue. Make sure to shake the bottle before measuring, as some separation is normal (especially if stored in cold place). Shake up your sprayer to mix it all together, soak plant from top to soil, especially underneath leaves where bugs hide. Some plants are more sensitive than others, so always start on the low end of that range for a couple days to make sure there are no adverse effects or stress on plants.
While it is not necessary, a good surfactant (like our Simple Soap Surfactant) boosts both area coverage and efficacy by reducing the surface tension of sprayed water droplets. We suggest 1-2 fl oz (30-60ml) per gallon mixed with Plant Bodyguard. Some growers alternatively or in addition use a similar amount of horticultural or other plant safe oil.
For most pests in the garden, you will want to treat for 2-3 days straight and then continue every 3-4 days for several weeks. Common troublesome pests like spider mites, aphids, and thrips may need more frequent treatment for up to a month due to their life cycle and laying eggs in soil or on plant. You can also spray a minimum dose weekly as a preventative measure, and use a light mixture as a cleaner for tents/greenhouses/etc.
For common fungal issues like powderly mildew, mix the same and application as above - but a higher pH in general of your mix (ie 8-8.5) will increase efficacy. You can do this through measurement and a bottle of pH up, or use more of a higher pH surfactant like ours to safely raise pH of spray solution.
In general, increasing air flow to your plants, making sure they have the right amount of lights/nutrients/water, and monitoring them for any signs of issues are the best first steps to prevention of issues in the garden.