If you missed last week’s inaugural basil grow journal post, it can be found by following this link.
This week, I planted the starter plugs in Hydro Korrels, the analogue of the now defunct Hydroton expanded clay balls. I chose this medium for its excellent capillary action, its low bulk density (relative heaviness) and its high porosity for air and nutrient solution holding purposes. The basil seedlings are fed nutrients via a top drip system that is connected to a pump on a timer. The seedlings are given a shot of nutrient solution at set intervals throughout the day. The top drip system sits in a 4×4′ Botanicare tray which rests on a table above a 40 gallon Botanicare reservoir. This set up was one third of the three part harvest system that I described and featured in a previous post about efficient hydroponic systems.
Seedlings’ nutrient requirements are quite low. The seed coat from which they burst contains ample nitrogen and other nutrients to sustain the growth of cotyledons (first leaf set) and the first set or two of ‘true’ leaves. However, I figured that a very low dose of a starter nutrient couldn’t hurt. I added 200 ml of Canna Start so that the plants have what they need as soon as they are capable of absorbing nutrients through their nascent root systems. I also added 200 ml of fulvic acid from the Fifth Season Gardening line for its chelating properties, its beneficial effects on nutrient uptake and the trace elements it contains. Finally, I added 80 ml of H2O2 (29% hydrogen peroxide) to help keep the water oxygenated and the reservoir free of potentially pathogenic microbes and other organic matter. According to my measurements, the reservoir contains around 150-200 ppm of nutrients (on the standard North American EC-500 scale) and a pH around 6.2.
As you can see the sprouts are still very small and delicate but their first true leaves are emerging and they will be photosynthesizing machines in no time. I recently bumped up their light from whatever ambient light could deliver to a 1000 watt MH bulb. This would be an ideal time to have a Lumatek 1000w air-cooled ballast as they can be turned down to as low as 400w for energy conservation purposes when the seedlings are so small. Savings could really add up with the ability to dial up your ballast with the growth capacity of your plants- not to mention the environmental benefits of using only what energy you require.
Until next week,