2017 Tomato Growing

All I can think is a 20l pot is pretty small and getting the watering and nutrients right will be a balancing act, at the height of the season you'll need to be watering twice a day with such a small root volume.

Have you a concrete base or soil beds in the greenhouse?

I've tried 42l pots and struggled with watering/feeding those compared to growing straight in the soil. Same goes for grow-bags, they are just too small, I have had better success growing in MPC 70l bags and doubling them up, i.e. one on top of the other with the plastic cut away inbetween.

 

I'd recommend Sungold and Black Cherry, both of which have performed very well for me over the very variable and difficult last few seasons.

Did you have shading?

 

Yes a fan would definitely help, I have one at 15 minute on/off intervals. Not only does it help keep it cool but moves the air about lessening the chance of diseases.

 

Far too early! Trouble with tempting new gardeners who then lose them to the cold, it will put them off growing in the future.

 

I reckon they should be okay, so long as there is plenty of air around them.

 

6 plants is good spacing. Why don't you mix the varieties, i.e. grow 3 of each in both the raised bed and the greenhouse - that will hedge your bets.

 

Not heard about that john558. I'd be interested if anyone has tried this.

All I remember, from years ago, when grow-bags first came out they were 100% peat and very acidic. The only way to grow anything in them was to add lime to get them to neutral pH.