[Wiltshire Worms]

I am getting a real greenhouse next year. I have just read JayG survey of tomatoes and I am wondering if it's possible to grow different varieties in 1 greenhouse or is cross pollination a concern.

[DD.]

Cross pollination is very unlikely as mostly they self pollinate within an enclosed flower. Cross pollination would not affect the flavour of the fruit, just the offspring from any saved seed next year.

[Wiltshire Worms]

Thank you

[GrannieAnnie]

I grow all my varieties in my polytunnel.  Never worried about them being cross pollinated.

The only ones that didn't grow true to type with the saved seeds were the Floridty but that's because they are an F1 variety. 

[Headgardener22]

As DD says cross pollination only affects the offspring if it occurs. I've also read somewhere that the varieties most likely to cause cross pollination are some of the determinate cherry varieties where the stamen go outside the flowers. I saw the recommendation was not to grow these varieties if one was interested in keeping seeds as they could cross pollinate up to 400m.

[cadalot]

So as my 100s and 1000s stood next to Gardeners Delight and I saved the seed from it will I actually get 100s and 1000s next year from the seeds?

[DD.]

You should do. There are only a few varieties that are an exception to this rule.

This gives you the full low down:

http://www.gardenorganic.org.uk/hsl/seed_saving/ssg12_tomatoes.php

[Headgardener22]

The reason I made the comment was because I grew some "Oleron Yellow" in 2012, saved the seed because they were the best tasting pale yellow cherry tomatoes I had ever grown. Unfortunately the plant I grew out in 2013 had red fruit so must have crossed with something. It wasn't potato leafed and as a cherry it didn't have double flowers so I don't know why it would have crossed. Just unlucky I suppose.

My plan next year is to grow a number of plants to see if any of the seed I kept has run true (I took it from a number of different fruit on different plants but then mixed them together).