Please do include your location or gardening zone in your posts. it is so easy to do and is of great help when trying to provide info.

In this case it would also be important to know the variety of tomato. Bloom size is often related to the variety's genetics.

Blooms may take several days to open fully and you don't indicate how old the blooms are.

The weather is the most likely explanation for the bloom performance and it is the weather - specifically the air temps - that will determine if they will set fruit or not.

The age of the plant also determines when the blooms will set fruit or not.

Dave

Hi Dave,

I dont indicate my zones as I dont like in the US. I live in Switzerland! We have had a strange spring with lots of rain (still raining) and night temps still sometimes below 10 c. Day temps are in the teens but have gone up to even 26 c on certain days. So they are indoors with me on a very sunny window with highs of about 26c and night temps of about 20 - 22 c.

Its a cherry tomato, tho i have no idea what kind. The buds have been forming for about 2.5 weeks and sort of opened about 2 days ago. The plants are about 11 - 12 weeks old approximately.

I hope this helps! Thanks again!

Ahh Switzerland. Even more important to include that info in your log-in then. Doesn't have to be a zone. Many of us use state names or abbreviations.

The fact that it is a cherry tomato explains the smaller bloom size since many of then, not all but many, do have much smaller blooms.

And if I recall my F to C conversions correctly the weather and those temps of mid 60s to lower 70s would go a long way to explaining the slow performance. With night time temps in the lower 50s those blooms will usually not set fruit.

You are going to have to wait for some warmer weather for the plant to really perform.

Dave

Switzerland could be anything from USDA zone 5 to zone 8!

A not-very-detailed map here:
http://www.uk.gardenweb.com/forums/zones/hze3.html

Thanks! This map is helpful. I am zone 8 then, in Geneva!

So this morning the first of the flowers fell off, entirely! so this confirms that there will be no tomatoes for me... :(

Another one just opened up wider today. Will I get any tomatoes at all? photo here says it better than i can.

http://www.flickr.com/photos/57048076@N06/7163853410/in/photostream

Clickable link to Raistlyn's photo:
http://www.flickr.com/photos/57048076@N06/7163853410/in/photostream

No need to despair: the top one looks good! Once a flower is pollinated, it's normal for the petals to fall, as they're no longer needed. Inside the green sepals is a teeny baby tomato, which won't seem to do much for several days. See this timeline for what happens when (note that there are 8 days between when the blossom opens and when he shows the visible tomato forming):
http://www.tomatosite.com/index.php?NT=Cultivation&RE=Truss_Timeline

When "blossom drop" occurs due to lack of pollination, the entire flower falls off: yellow petals, green sepals, and about 1 cm. of the green stem. [There's a natural joint in the stem where this occurs. If you try to peek inside the sepals to see the baby tomato, the joint will sometimes break accidentally, so be gentle.]

Lucky you to have such an obvious zone as Geneva! The USDA updated our zone map earlier this year and it took me quite a while to determine that I'm probably a mile or two on the cooler 7a side of the line.

Oh thank you for th� info and encouragement!

when I see photos of tomato fruit developing, the cone shaped part of the flower kinda stays there even while the petals fall off. Mine has lost everything except the sepals, but certainly doesnt look like blossom drop hmmmm confusing! When I peeked inside just now *i think* I saw a teeny weeny green pin head inside! Could that be.... .??

Also according to the link you sent, it seems the flowers are open for quite a few days before falling off. I think mine have barely been open for 2 days ! I wasn't afraid of lack of pollination actually as I have been shaking them everyday, but more blossom drop due to unsuitable temperatures.