Tomatoes: fruit set

[beavis]

Worried about tomato fruit set:

Is it too early in the season to worry? Most of my plants were transplanted into the ground in late February/March and they have grown into monsters so far. Some of them are over 4 feet tall already!

This year when I enhanced my garden beds, I added a lots of horse manure to the soil delivered from a nearby farm. For the most part, I believe it was pretty well composted, but once I observed a part of my large pile of compost smoking after I shoveled into it. But that was only one time, it truly looks like soil.

Here is a list of the recent daytime/nighttime temperatures:

67/48
67/47
66/48
72/44
71/52
83/41
81/43
72/48
78/38
79/33
82/35
91/38
90/41
87/41
79/40

Is it still too cold to set fruit?

There are flowers, and in one of the pictures there is a single tomato fruit growing..

thoughts?

 

[thistlebloom]

For what it's worth Beavis, nearly every night here last summer was in the forties and I got tremendous fruit set. I only picked two ripe tomatoes, but that's another story. I confess to cheating and using the blossom set spray (can't recall the name ) so that probably had a lot to do with it.

ETA: Your tomatoes are a lovely sight!

 

[beavis]

I think I will try some blossom set spray thistlebloom, great advice!

That correlates well with this I learned:

The failure of tomatoes to set fruit
is a common problem in California in
the spring and early summer months.
Evidence to date indicates that low
night temperatures, high day temperatures,
poor soil moisture conditions,
faulty nutrition and insect or disease
damage may adversely affect fruit set.
The supply of available food within the
plant also has a bearing on fruit set. For
example, a period of heavy fruit setting
is usually followed by a period of poor
setting.
Low temperatures, particularly at
night, appear to be one of the main
causes of poor fruit set in California. On
young, vigorously growing plants the
processes leading to fruit set are impaired
when night temperatures fall below 60" F.

 

[thistlebloom]

Beavis, it's interesting that some of your warmest days had some of the coolest nights. Were those Santa Ana days? I wonder if the dry air has anything to do with a cooler evening?

 

[beavis]

they were santa ana days. we had gusts 25-30 mph during the day. So lack of nighttime cloud coverage probably lowered the nightime temps.

 

[lesa]

The plants (and your garden) look incredibly healthy. Those nighttime temps are just chilly for those delicate fruits! Here's hoping your evening warm up a bit. Good luck!

 

[hoodat]

I'd also put it down to low night temps. Most varieties set fuit best with night temp in the high 40s to low 50s. Blossom set should do the job till your nights warm up.
Our recent Santa Ana got pretty hot but thank goodnss we didn't have strong winds. It was actually harder on my rabbits than my garden.