What Soil/compost Do I Use For My Window Boxes To Grow Vegetables?

Question

Dear Sir/Madam, I’m a primary teacher and I live in London in a council flat and have very little space – but I am ambitious and motivated! Every ground floor flat does have a little area (see photo) which is about 3 metres long and 15cm wide of space for growing. As shops are mostly closed at the moment I was limited to the seeds and soil I could buy. Today I have sowed some tomatoes (3 varieties), onions, peppers and chilies in pots and keeping most indoors for now to germinate. I also have some lettuce, rocket, basil, parsley, coriander and a few flower seeds (including lavender). Please advise me on how I construct my bed/box best for growing mainly vegetables. Can I use compost only? When can I put the seedlings outside? The depth of the bed/box is about 15cm – is this deep enough? I bought coco coir bricks – are these any good? Seemed very cheap! I have grown things in a different flat for the past 3 years with varying success but I have never used an area like this before. Any help would be much appreciated! I am involving 2 young children who are very excited about it also.

Answer 1

I would encourage you to use commercial potting soil and give each plant a little boost of compost in it's own spot. The main thing you need to be sure of is that there is good drainage – your soil as well as the planter should be well-draining so your plants' roots don't sit in soggy soil. Coir should be helpful with this.

It would be a challenge to answer all these questions in an email, so I'm going to refer you to a few specific articles that will help you with your project:
https://www.gardeningknowhow.com/edible/vegetables/vgen/companion-vegetable-garden.htm
https://www.gardeningknowhow.com/edible/vegetables/vgen/incompatible-garden-plants.htm
https://www.gardeningknowhow.com/edible/vegetables/vgen/starting-indoors-direct-sowing.htm