Raised bed on tile floor, covered veranda?

Question

We live in an apartment with a huge veranda. I'd like to build a simple raised bed out there to grow some herbs and a few veggies (tomatoes, cucumbers, peppers).

If I put in a layer of gravel at the bottom, I believe drainage will not be an issue, but should I build some sort of a drainage chute to take the water to the gutter? I don't really want it seeping all over the veranda where we eat dinner, the kids play, etc.

I'll also have to water the bed myself since the veranda is covered by a roof (high enough that the veranda gets plenty of early morning and late afternoon sun). Will there be any problems or a benefits to that?

The veranda is approx. 50m2 (which I believe is around 500ft2) and the floor is concrete with porcelain tiles on top. I was thinking of building just a small bed, around 1x3 metres or something like that. I'm flexible. Depending on the positioning, it can either get direct sunlight from around 8am-11am, or from around 3pm to 6pm. Both times the sun is low (rising or setting).

I'm in the southern hemisphere, "Yearly temperatures average between 9 and 35 °C (48 and 95 °F). The Köppen climate classification of the region is tropical savanna climate (Aw) and it borders on a humid subtropical climate (Cwa)".

Answer 1

Unfortunately you WILL have drainage issues. The rock or gravel at the bottom will be causing a PERCHED WATER TABLE essentially causing the soil to super saturate before any movement of water happens into the gravel. This is the same reason one should never put rocks or gravel beneath the soil and above the drainage hole. JUST potting soil, no rock or gravel!

Please send pictures. Also hoping you haven't purchased plants because we could help you select plants that will do best in this location. To include vegetables, annuals, perennials, shrubs etc.

Went back to read your question and am thrilled you've asked this question before installing this planter! Pots you can purchase work very well for vegetables especially GROUPED. Hope this reached you soon enough as spring fever is a pandemic this time of year! You should consider a few perennials or a woody shrub or two in addition to vegetables. Need to see the orientation of your patio and purchasing a few great pots of different sizes with holes, 'pot feet' and great potting soil without water holding gimmicks or fertilizer is a great start. The pots should be all one color, or one shape, or in some way similar to each other. Perhaps enough for 2 groupings.