Here are a few things I learned during the first serious gardening season on my terrace. Previously I have been cultivating on land and in easily movable pots in a quite different climate. Here in Germany I’m on a rooftop terrace with a mix of fixed (at least for the season) garden beds and some larger pots. This year was the first serious test of growing some vegetables up there. Last season I just had a few fruit trees/bushes and some strawberries in pots.
It has been a journey of both successes and backlashes. I feel proud to have managed to grow a few cucumbers in such a dry spot and that I managed to get some cauliflower going, which isn’t really the easiest. The zucchini loved its low and slightly dry bed (it’s still giving more fruit!) while other plants definitely could have done better. For some reason the strawberries have been tiny this year. I’m not sure if it’s due to the type or if the climate was making life difficult for them this season. Last year they were thriving and producing a lot of berries.
In this article I want to share some of the things that didn’t go so well this year and what I have learned to prevent it for the coming season.
1. Never underestimate the power of the tomato
Some tomatoes grow big. Really big! Since I bought a few tomato plants at random in the gardening center I wasn’t sure what to expect. They all turned out to be high growing varieties and I didn’t have a frame high enough prepared on my garden bed. I used some spiral plant supporters to help carry them up, but this just wasn’t enough. They are growing high and wide and producing a lot of tomatoes, so the plant supports started tilting sideways and are nowhere near high enough. I guess I shouldn’t complain about getting loads of tomatoes, but it’s hard to figure out a smart way to support the plants now that they’re already looking like a jungle and are all tangled up in each other.
What I will do for next year is building a proper frame with wires to tie the plants to. It has to be at least 150 cm high and it will be attached to the inside of the raised bed to make sure it’s stable enough.
Another small tip I can add here is don’t plant your basil between the tomato plants. Make sure it’s placed quite a bit in front of them. Now my basil perished due to ending up in the shadow of the thriving tomato plants. Yes, I probably could have moved it but I thought of this too late.
2. Be quicker than the small white
The small white or cabbage butterfly loves plants of the brassicaceae family. I found out the hard way through having almost all of my cabbage plants infested with its larvae whilst being away for a weekend. It’s not such a big problem on my kohlrabi or the cauliflower since they mainly went for the leaves, but my savoy cabbage has holes all over. It did re-grow some new leaves once the larvae had hatched, but it’s nowhere as big and pretty as it probably would have turned out hadn’t they chewed away on it…
For the coming year I will cover my cabbage plants with fiber-cloth to protect them. That should hopefully do the trick.
3. There is such a thing as too much sun
Roof terraces have one big flaw and that is that they are usually exposed to quite harsh sun and wind. This makes your pots or raised beds dry out quickly. Sure, my terrace is directed north so the house is shading part of it during the day. But during the summer months the sun still stands high enough to shine straight onto several of my raised beds almost all day long. That in combination with strong wind means that water evaporates quickly.
I did build some of my beds with only one row of boards since I wanted to try out how different plants would react to it and how fast they would dry out. It works fine for plants like zucchini and the strawberries which don’t have very deep roots and/or can stand drying out for a bit. But for other plants they definitely dry out too quick.
The remedy for this during the next season will be adding one more row of boards to provide deeper soil as well as adding a lot more mulch to the surface to prevent evaporation.
4. Plan for a longer gardening season
By now in mid August everything but the tomatoes, the pumpkins and the apples is ready to harvest. Now what? I guess I have to go buy some more plants to have some nice green features out there on the terrace.
A few herbs should be possible to sow again and have ready for later in autumn, but for most vegetables the season will be too short. I’ll give it a try with some spinach and radishes too, but besides that I don’t expect much.
Next season I will make a sowing schedule to make sure that I add plants gradually to have a longer gardening season. That requires that I leave some space in the plan. Until now my raised beds were packed with plants.
5. Don’t buy cheap-ass seeds
I wanted to try out how well some seeds from a discount supermarket worked out. Some of them sprouted fine, some turned out to be something different than was stated on the seed bag and some didn’t grow at all.
I don’t think it has to do with too difficult conditions since I was successful even with plants that are quite complicated to draw up. My guess is that it’s really just low quality seeds. I will try out some of them indoors later in autumn just for fun, but I don’t expect many to be successful.
The conclusion is that cheap seeds don’t turn out very cheap in the end. Some of them are alright, but it’s better to invest in quality products or save the seeds yourself from tasty plants you eat.