Pre-Season Tomatoes For Best Flavor

Print Friendly, PDF & Email

Fabulous tomatoes are a little sweet and a little salty

Build Brix With Compost, Then Add Sea Salt

Given that the Maritime Northwest is not exactly prime tomato territory, it’s not super surprising that I’m often asked for tips on growing tastier tomatoes. From soil temperatures and nutritive quality to the varieties we’re growing, there are quite a few factors that influence the flavor of all fruits and vegetables. For starters, planting heat lovers in cold soil is enough to stunt their growth, and can even cause them to lose ground a bit. Grown as annuals in this climate, tomatoes have just a few months to develop to their full potential, and even a modest check can make a big difference to overall performance.

In addition, both over-watering and using high nitrogen fertilizer can dilute food crop flavors. Italian farmers traditionally teach that tomatoes must be grown on the dry side to develop the boldest flavor. What does that mean? Early in the season, water weekly as needed, carefully wetting down soil only, since foliage diseases love wet leaves. By August, allow the top inch or two of plant soil to dry out between waterings. By late September, letting foliage start to wilt a bit (not completely) between waterings will persuade the last fruits to ripen fully.

The Tasty Role Of Compost

When planting tomatoes, mulch generously with mature compost to bring out the best of their natural flavors. Compost mulch is as important for good tomato flavor as fertilizer, because it helps plants build and store natural sugars called brix. Brix is a measurable indicator of sugar content, and high brix counts give every edible from tomatoes to turnips a more nuanced and complex flavor profile. Compost also improves soil quality and texture, making it easier for roots to penetrate dense or airy soils, and promotes strong, sturdy plants by encouraging vigorous root growth. Roots are sometimes called “plant anchors”, keeping them upright while keeping them well nourished, and wide ranging roots can glean water and nutrients even from poor soils. Since most compost is close to pH neutral, it helps to balance acidic or alkaline soils as well (many edibles prefer pH neutral soils).

Such assistance in providing plants with nutrition is especially important for tomatoes, which are what’s known as gross feeders, meaning they require a lot of food to succeed. Tomato plants in pots will need frequent feeding (as in every 10-14 days), because fertilizers get washed out by repeated waterings. Plants in the ground can spread their roots a lot further, so feeding them once or twice a month is plenty. Where weather is unpredictable and variable, don’t rely on pelletized time-release fertilizers, as they don’t work when soil temperatures are below 70 degrees F. Instead, supplement both potting soil and garden soil with compost, and use natural fertilizers that combine quick and slow-release foods.

Pre-Seasoning With Sea Salt

Besides offering my tomato plants a mild, balanced organic fertilizer, I also give them kelp meal and/or a liquid seaweed extract. When tomato stems break before the fruit has a chance to ripen fully, the problem may arise when we use inadequate water-soluble fertilizers, especially common when tomatoes are grown in pots. Liquid seaweed extracts help strengthen weak stems by supporting steady plant growth even when cold nights follow warm days, a notoriously unhelpful occurrence. As a liquid or as meal, kelp combines micronutrients and trace elements with plant hormones and growth stimulants that promote root growth, improve stem and foliage density, and increase chlorophyll production. Kelp extracts also contain traces of sea salt. Aha!

For years now, I’ve enjoyed amazingly flavorful tomatoes, thanks to a strange little “secret”; pre-seasoning with sea salt. Surprisingly enough, a single dose of salty seawater (1 cup of seawater per quart of tap water) can greatly improve tomato flavor. After recently recounting this to some friends, I realized that I was forgetting how I came up with that recommendation, and dug out my old research notes. Here’s the story: For about a century, New Jersey was one of the top tomato growing regions of the USA. However, about 20 year go, those famous tomatoes were losing their savor. Eventually, various field trials and studies revealed that changes in commercial fertilizer ingredients had resulted in reductions of measurable sodium in the rich New Jersey soils.

A Little Salt, A Little Sugar

Though too much salt can kill plants, they need a little bit to develop their fullest flavor. Where soils retained sodium, tomatoes had greater variety and concentrations of the sugars and acids that influence the tomato flavor profile. As every Italian cook knows, a rich red pasta sauce needs both a pinch of salt and a pinch of sugar to come into balance. The farmers found that adding compost to soils helped plants build brix, and amending salt-stripped field soils with mined sea salt boosted soil levels of sodium, chloride, and many other minerals in trace amounts. Rather than soaking their fields with seawater, farmers use an agricultural product called SEA90, a version of which is available to home gardeners as well. Once the sweet/salty soil balance was restored, so was the robust, bold flavor of those famous tomatoes.
Home gardeners who don’t live near a source of fresh sea water can find a wide range of sea salt and mineral soil supplements here: 

As one researcher reports:
“For growers interested in conducting a small trial to evaluate the effect of salt fertilizer on tomato taste here is a suggested protocol: Use 46 grams of to treat an area 4 square feet or land area needed to grow one tomato plant. Apply the treatment by mixing the SEA-90 product into the soil at time of planting. Flag the treated plant and perform your own personal taste test by comparing the treated fruits to other fruits of the same tomato variety from another part of the field. Leave some border space between plants when sampling fruits for comparing treated and untreated plants.

An alternative approach is to use sea water from the Atlantic Ocean. {Or Pacific, of course} 1300 ml (or 0.35 gallons) of sea water contains about 46 grams of salt which is enough to treat one tomato plant. Apply this seawater as a soil drench around the base of the plant two weeks after transplanting. To prevent leaf burn, do not allow the seawater to touch the leaves.”

Onward, right?


This entry was posted in Care & Feeding, Planting & Transplanting, Sustainable Gardening, Tomatoes and tagged , , . Bookmark the permalink.

2 Responses to Pre-Season Tomatoes For Best Flavor

  1. Diane says:

    Thanks Ann,
    Given I always grow several tomato plants annually. Any advice is greatly appreciated. And thank you for talking about growing plants in pots. I rarely see any information about how to make that work better.
    Saltwater huh…we’ll we certainly have that at our disposal.
    Question: if I get a gallon of salt water does it have a length of time it can be saved?
    Thanks Ann,

    • Ann Lovejoy says:

      Hi Diane, I’m thinking seawater is pretty stable in terms of this kind of application, but since it’s so close at hand for us lucky ducks, I’d say try to use it within a week or so. It’s really the minerals we’re after, not bacteria and in compost tea, so I’m guessing it will be fine for at least that long.

Leave a Reply

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