Plant them in a jug or other container and leave them outside. See the Wintersowing Forum.

Direct sowing is very iffy. Seeds get eaten, they are food. Birds, critters and insects are all hungry. Seeds can washout, downpours in harsh storms can dislodge the seeds and wash them out of the soil. Do you know what tomato seedlings look like and can you differentiate them from weed seedlings which will sprout in the same soil?

When you WS, bringing in sprouted seeds at night equals coddling. I am not keen on coddling seedlings. WS is all about climate-hardy seedlings. I choose to leave the flats outside--if you want you can throw a blanket over the flats in if night temps will drop under 30F, then remove it in the morning. Visit the WS forum here at GW, and read about the method in the FAQs, ask folks in the forum for their advice, and see if this seasonal germination method will work for you.

Here is a link that might be useful: WS forum

Honestly, if you rarely see frost, I don't see an issue in direct sowing. We do get frost in my zone, and I know several people that direct sow in the spring, with good results. Never hurts to try, and you could always just start the seeds in post, bring inside on cold nights, and transplant in the spring.

Every year my volunter's catch up to the greenhous plants.

I have "volunteers" sprout most every year around Feb. from tomato's that were missed when cleaning up the garden in the fall. These prove to be very hardy plants, although I'm never quite sure what they are, so I usually let a few grow & call them either cherry or regular. (in fact, some just sprouted this week!)
The problem is BUGS & birds enjoy the little feast since there is not much else left for them.......... LOL
The few I want to "save", I transplant to containers or leave in place & at night cover with a gallon water jug that has the bottom removed until they are big enough to survive on their own.
COS: I am overwintering 1 Jalapeno plant that is still producing pods & has survived 2 - 28 degree or less nights (so far)!
All in the ground, grown in real "dirt"

Regards, T.......

Grew up in Whittier and never had a problem starting tomato plants in the garden from seed. In Southern Cal there is normally plenty of food available for the birds and rodents that they don't have to go digging for seeds.
You might want to put a cover over them to protect them from heavy rain till they sprout and get established. Ami

One comment from another Orange County grower, I planted a good selection of cool climate varieties early this fall and for one reason or another, almost all of these plants are dead and most did not bear significant fruit. On the other hand, in my squash bed I had a few tomato volunteers sprout, I totally ignored them and just yesterday I picked some delicious fruit. Of course I am not sure of the varieties, but they are probably Stupice or Glacier.

But the implication seems to be that seeds know what they are doing. They know when to sprout and when to grow. It seems like direct sowing has something going for it, indeed.

Gary

I allowed some volunteer plants to grow along a fence line last season. The soil had not been prepared, had no added nutrients, was hard as a rock, and received no supplemental water. The volunteer seeds sprouted in mid April which was about two weeks after I planted my "grown from seed" seedlings in my raised beds. Throughout the hot, dry summer, the volunteer plants received no care. By the end of summer, the volunteer plants considerably out performed and produced over the raised bed tomatoes.

My belief is the raised bed plants experienced root disturbance during up potting and planting causing a rootball of fibrous roots to develop without a main taproot. The volunteers did not experience root disturbance resulting in a tap root that penetrated deep into the soil. That is the only way I can explain the volunteers never needing additional moisture or nutrients during the hot, dry summer.

Tx

YOUR area is different...but WHERE I live...you would NEVER get tomatoes by "direct seeding"...too cool and growing season is too short. Fine for Corn, Beans, and Squash...NOT 'maters nor peppers. AND, to get RIPE fruit... I've got to use a "short-season" variety here in the "High Altitude Desert".
Unfortunately..this ain't the Southern California Coastline, Baby.
BUT, good luck trying it. Here...I wouldn't waste my time with THAT idea.

If your volunteers are doing better then you're not taking proper care of your plants. It's not because of a tap root, tomatoes don't have tap roots IME.
If your plants get rootbound in their pots they've been in those pots too long and it will help to break up the root ball. The best way is to pot up if the weather doesn't cooperate.
I wouldn't get much fruit if I direct sowed but you should be able to do it in So.Cal. I did it when I lived in Coco county, just east of frisco.

bahacca,

I live in Central Oklahoma, but I am originally from North San Diego County. My family always grew tomatoes and peppers by direct sowing the seed and got great bumper crops. The plants tend to be hardier and have thicker stems.

I do the same now that I live in Oklahoma, but to prevent the seeds from washing, I bury bottomless milk jugs in the soil where I want the plants to grow. Sprinkle in three seeds in each pot and water into the soil. Don't cover them with soil
.
When the seedlings get two or more sets of real leaves, pull out the 2 weakest looking ones and discard into you compost bin or transplant elsewhere if you wish.

As the plants grow, the plastic jugs act as wells for feeding and watering. You can remove them easily later on if you wish. The sun causing the plastic to break down.

I also grow cabbage and broccoli this way and get great plants. It's not necessary to remove the plastic bottomless pots you grow the cabbages and broccoli in though. It actually supports them off the ground and keeps them cleaner and freer from exposure to soil-born diseases.

I have grown my veggies in containers and nursed them through the winter months, with grow lights and heat and done all the repotting as they grow, and then exposing them daily to harden them off and all that rot. It is a lot more work. In addition, you have the added problem of dampening off and losses from other causes. All that pampering just adds to the cost of growing them yourself - a total pain if you ask me. I have not lost any to dampening off when growing them directly in the soil.

Try it both ways and see which way works best for you.

~Annie

An update for those interested: I planted 4 seeds of each variety I had. Black Cherry got knocked over by my dog, so they don't count. All other varieties sprouted and grew. Average of 75% success rate. I planted the seeds, 4 to a small pot, and set them outside 24/7 in January.
I transfered the strongest into the ground in March. Orange Strawberry and Arkansas Marvel were eaten to the ground overnight. All the others are doing great.
As for volunteers-I allowed one to stay from last summer, he overwintered and this is him today:

Talk about direct sowing. This volunteer was found in the sand in Basrah, Iraq. I wanted to take it home with me when I left as the most badass tomato plant ever.