How to Grow Tomatoes in Cool Coastal Climates

how to grow tomatoes in cool coastal climatesThe Central Coast of California has a lot going for it, but being able to grow a great variety of tomatoes is not one of them. Cool foggy summers make getting a great harvest difficult, but it’s not impossible. By selecting the right varieties and planting them correctly, you can have a pretty good tomato crop this year.

Varieties to grow

Because our summers often seem cooler than our winters, selecting the right variety of tomato is important. Choosing varieties that will produce in a short season or those selected for colder climates, seem to produce the best results. Some varieties that produce reliably on the Central Coast are:
Salad and slicing tomatoes
Early Girl
With only 52 days until harvest, Early Girl is a very reliable, medium sized, indeterminate tomato. Sure it’s not as flashy as some heirlooms, but what good is all that pizazz if you don’t get any tomatoes?
San Francisco Fog
As the name implies, San Francisco Fog is well adapted to our cool summer. Another indeterminate tomato that produces tasty, medium sized fruit in about 70 days.
Although Stupice produces smaller (2 oz.) tomatoes, you get plenty of them. Ready in about 52 days it’s a great cool season producer.
As the name implies, Glacier is a determinate tomato that is well suited for the cold. It’s 2-3 oz fruit is both sweet, flavorful and ready in about 58 days.

Cherries and Romas
Sweet 100, Sweet Million, Super Sweet 100 all produce an abundance of flavorful, bite-sized red fruit.
Sun Gold. Hands down the best yellow/orange cherry tomato I’ve grown. Ready to harvest in about 60 days.
Black Cherry. Not as prolific as the others, this cherry tomato offers a more rich, complex flavor that I’m willing to make space for.
Roma, Martino’s Roma. Romas always do well. Great if you want a cooking and canning tomato.

Heirlooms and Colors
Not as prolific and reliable as some of the above tomatoes, but they are so hard to resist.
Brown Sugar. Juicy, sweet with a strong tomato flavor, this indeterminate tomato is ready in about 70 days.
Sara Black, Black Krim. There is just something about the strong flavor of black tomatoes. Both of these will give you some production late in the season.
Lemon Boy. A pretty and reliable yellow tomato.
Cherokee Purple . A favorite at some of the community gardens this tomato does a good job for us.

When to plant
Those first few warm days in early spring make us want to dig right into the garden but for tomatoes you want to wait. Tomatoes will not set fruit until nighttime temperatures are above 55 degrees. For us on the Central Coast, that happens some time around July. Sure you can plant your tomatoes early and get a lot of growth and they will bloom. But then you will watch the blossoms drop off again and again. At that point all you are doing is allowing the plant to put on vegetative growth and in a drought year especially, that makes little sense. Why spend all that time watering and fertilizing for leaves? I never put my tomatoes in the ground before April.

Where to plant
As you now know, warmth is key to producing great harvests. Finding the warmest spot in your yard can give you a bit of an edge on tomato production. Locating a nice sunny spot that is protected from strong winds or a spot that will get some reflected heat can improve your harvests. Plus don’t forget to plant some borage nearby.

How to plant
I have planted them deep, placed them on their sides and planted them just as they came out of the pot. Honestly, I haven’t found one method to be superior to the other. What I did find that made a huge difference is how close I planted them. Don’t crowd them. In areas that have wet foggy mornings followed by warm afternoons, fungi and diseases flourish. Crowding your plants mean they stay wet longer and the close proximity increases the spread of disease. What you want is a good amount of air circulation between the plants. One way to accomplish this is to spread your tomatoes around the garden and plant lower growing crops like lettuce and basil in between. It is also important to stake or cage your tomatoes. Staking requires a bit more labor and attention but does seem to produce the most disease free (good air circulation) plants. If you use cages, get the largest tomato cage you can find. The tiny cages will always wind up being too small for your mature plants and you they become cramped as they grow.

I prefer to do things organically and like Dr. Earth Tomato, Vegetable & Herb Fertilizer. It is a nice, slow release fertilizer that I put out a couple times a season and let it do it’s work. Brand is not, however, as important as the amount of nitrogen. Avoid fertilizers with a high amount (the first number) of nitrogen. Too much nitrogen causes plants to put out more leaf growth and less fruit production. They can also lead to problems like blossom end rot. For this reason, I also avoid planting tomatoes in soil that contains added, non-organic fertilizers. Most of these potting mixes are designed for flowers and not tomatoes and again contain too much nitrogen.


While the plants are getting established, I normally water them twice per week. Once the plants are about a a foot high, I reduce that to once per week. Too much water will cause tomatoes to put out more leaves than fruit. To keep some moisture in the soil in between waterings, I mulch with a 3″ layer of straw. How often you water will be determined by the weather and your soil. The key is to let the soil start to dry between waterings. If you stick your finger down into the soil an inch or two and it still feels moist, check it again the next day. Keep waiting a day until the soil starts to feel dry, then water. During particularly hot days, you may want to check the soil a bit sooner. By doing this, you will soon get a feel for how often you will need to water.

Tomato plant photo by Steven Reynolds used and adapted under the Creative Commons license found here.

Related Posts Plugin for WordPress, Blogger...

4 comments for “How to Grow Tomatoes in Cool Coastal Climates

  1. Morgana
    at 1:56 pm

    Super helpful! Thank you!!

    • Kat
      at 5:58 am

      Good luck with your tomatoes!

  2. Sara G Michel
    at 9:09 pm

    We grow in coastal central California with morning fog every day. This is very helpful! Thanks!

    • Kat
      at 6:13 am

      When I first moved here from So. California and got into this cooler climate I was thrilled to get gardening, but I found this climate has its challenges too. Good luck with your tomatoes.

Leave a Reply

Your email address will not be published. Required fields are marked *