Experiences with my setup for germination in the 2012 season were great, so I started out the same way in 2013 with best expectations. I got heavily disappointed and re-did the setup for germination, which then worked out fine in the end. Once the seedlings had popped, I nursed them for six weeks in a DIY grow-box with artificial light (2x 18 Watts fluorescent tubes with a colour temp of 6500 Kelvin [Osram Lumilux Cool Daylight 865]). Then the plants got potted on into one to 1.5 liter pots on a bright windowsill. In mid April when – in terms of weather – spring finally arrived in Berlin, I put the plants out onto the balcony and into their final pots (5 – 35 liters). The balcony is in fact a so-called loggia facing south. So it’s a half-open space which protects the plants from hailstorms and similar weather-threats but still lets them have enough sunlight.
My plants go through three potting-stages, and I use a different soil-mix for each of the stages. For their time in the grow-box, I use off-the-shelf starter-soil (fluffy consistency and low in nutrients). During their second stage in the one-liter-pots, the plants grow on a mix of three parts regular potting-soil, three parts starter-soil and one part earthworm-castings. Then in the final pots the mix changes to four parts organic, peat-free tomato-soil (Neudorff Neudohum), one part earthworm-castings and five grams of Guano per liter of soil-mix. Throughout the season, the plants will be fed with organic (i.e. slow-release) fertilisers only, chiefly Vermicompost (earthworm-castings), Guano and Vermicompost tea.