When surfing the internet for information about growing tomatoes I am always amused when I read "tomatoes are easy to grow". It is true that they are easy to grow if you've had several years of experience and know what not to do ... especially with regard to stopping infection and disease recurring from previous seasons.
For those who are new to growing tomatoes, among the biggest mistakes made are over-watering and over-feeding. Too much water and their roots won't develop fully and too much food can also damage roots and prevent the uptake of the entire range of nutrients needed to develop a strong healthy plant.
The weather also plays a big part in success and failure, especially when growing outdoors.
Some seasons everything goes well and tomatoes just appear like magic ... you feel as if you could throw a seed out of the kitchen window and get tomatoes four months later!
Other seasons you try very hard and the results are disappointing.
I think it is better to say that "tomatoes can be easy to grow".
Micro Tom on the windowsill (pic right) ... one of the easiest varieties to grow but the fruit is quite small. Tumbling Tom and Garden Pearl are among the best cherry varieties but will require a large pot or container and a sunny position in the garden.