Monday, July 22, 2024

Thanks for the memories! May 2010-March 2020

Get the local dirt in our northwest corner • Regrowing in 2023!

Best Tomatoes: Tips for growing a NW favorite

May 14th, 2010 | Category: Growing

by Chuck McClung

Tomatoes are one of the most popular garden vegetables all over the country. Everybody wants to grow tomatoes. Certainly, the best tasting tomatoes are home grown. That distinctive fragrance of a tomato plants’ leaves signals that warmer days are back again. Many derive their inspiration for gardening solely from the possibility of growing their own tomatoes.
But so many beginning gardeners in our area are greatly disappointed by their tomato growing efforts. Why? Why do tomatoes seem so “difficult” to grow around here? What can we do?
For many years, I’ve had great success growing tomatoes in Whatcom County. Through a bit of trial and error, as well as comparing notes with other tomato growers, I’ve learned that anyone with lots of sun and who waters their plants can grow tomatoes in the Northwest, with a few helpful hints.

Getting Started
Tomatoes require warmth, sun, and moist well drained soil. We experience a cool, short growing season with little summer rain, basically the opposite of what tomatoes prefer. Our cooler climate also breeds many diseases, especially “late blight” for tomatoes. Therefore, we must adjust our gardening techniques to match our Northwest climate.
Select a location in the garden that receives as much direct sun as possible. If you have only half day sun, plant in areas that get afternoon sun, the warmest part of the day. In containers, use the largest pot your space will accommodate and nothing smaller than a five gallon pot.
Amend your soil with organic matter or compost, avoid lots of manure, and be sure you’ve provided an easy way to water! Planting your tomatoes in a different location each year helps keep away late blight.
Keep in mind, by the time the ground is warm enough for tomato seeds to germinate outdoors, there isn’t enough growing season left for the plant to produce ripe tomatoes. So you must start your own tomato plants from seed indoors or simply buy started plants.

Seeds vs. Starts
By the time you read this, it will have been too late to start seeds; for this year, you’ll have to buy started plants. For next year, however, consider the options.  By starting your own seeds, you’ll save money and be able to select the healthiest plants from the seedlings. You’ll need direct sun indoors or a grow light to keep the seedlings robust and healthy until they can be transplanted outside. If you lack direct sun indoors, and do not want to buy a grow light, buy starts.
Tomato seeds should be started indoors 6-8 weeks before your last frost. That’s a big time and space investment to grow a young, healthy tomato plant to transplant outside. Sometimes simply spending $1.50 for a started plant is worth the time saved, especially if you have a small garden.

Planting Tomatoes
The presence of the water and mountains produce an incredible diversity of microclimates in the Northwest. Generally those closer to the salt water experience a longer growing season and an earlier last spring frost. Some areas in the foothills of the Cascades, however, can get frosts in late June.
Wait until after your last frost to plant tomatoes outdoors. In Whatcom County where I live, May 15 is generally considered the guaranteed last frost date. If planting before your last frost, protect your young tomato plants with frost blankets, cloches or cold frames.
Dig and amend as big of a planting hole as you can, and use organic, slow release fertilizers. When planting, bury the bottom of the stem. Tomato plants will root along any part of the stem that touches the ground.
Most tomatoes are “vines” and require support to keep branches off the ground. “Tomato cages” act as a frame and support the stems. Plants can be also be staked with a 1-inch x 2-inch” cedar stake as a minimum size. Get creative; I’ve seen some enterprising gardeners tie strings from the eaves of south facing walls as support for tomatoes plants.
However you decide to support your plants, start doing this the same day you plant. It is well documented that vining plants, as vague as that term is, grow more vigorously when provided support. In our cool, short season, we want tomato plants to grow and fill out, flower, and produce tomatoes as quickly as possible. Even with tomato cages, I tie the young plant to a stake until the size of the plant fills the cage.
Tomato stems will grow quite thick during the season and ties like string, tie tabs, and rope will girdle and cut the stem as it expands. I find that a roll of that half-inch wide green plastic tie tape for $1.99 works best.

Continued Care
As the plant grows, continue to tie the stem to the stake, about every 6-10”.  Tie the stem with the green plastic tie tape snug and tight, right up against the stake.
Always remove any leaves that touch the ground. One of our key ways to reduce the incidence of late blight is to always keep water off the foliage. By removing the lowest leaves on the plant, rainwater won’t splash the soil on the foliage. Some gardeners cover their tomatoes with clear plastic during periods of rain in late summer and early fall during cooler weather.
Furthermore, remove any side branches from the developing plant on the bottom 12 inches of the main stem of the plant. New side branches may grow from the same location again; keep pinching them and they’ll eventually stop growing back.  With side branches up off the ground air moves better under the plant at ground level also reducing the incidence of late blight. In addition, with the low side branches removed, the plant will put more energy to growing up, which is what we want in our cool, short growing season.
Tomato plants require more water as they grow bigger, the days get longer, and the daytime temperatures get higher. Never use overhead sprinklers, because, as mentioned earlier, we don’t want water on the foliage. Soaker hoses, drip systems or hand watering works best because the soil is watered not the plant. Watering in the morning is best, but watering after work or in the evening is better than no water at all.
Once plants reach 5-6 feet tall, prune the ends of the branches to prevent them from growing taller.  In this way, more of the plant’s energy is allocated to setting and ripening fruit. This is again a cultural procedure to adjust to our short cool season. Continue to prune tops of any branches that exceed 5-6 feet tall.

Harvesting Tomatoes
What a ripe tomato looks like depends on the variety. One way to check ripeness is to look for the “bent knuckle” on the little stem that supports the tomato. If this knuckle is slightly spread apart, a ripe tomato will immediately pop off. Store tomatoes at room temperature in the shade; they lose flavor when stored in the sun or refrigerated.
Near the end of the season after the first light frost, all green tomatoes can be harvested from the plants and allowed to ripen indoors. I put all my late season unripe, green tomatoes in boxes, and wait. Not all will ripen, but you’ll be surprised how many will, and they’ll taste so good.

Tomato Varieties
So those are the basics of tomato growing. The other half of the tomato growing puzzle is to select early maturing, disease resistance varieties appropriate for the Northwest. Several years ago, I had large garden plots where I experimented with a couple dozen tomato varieties each year. I gained a lot of experience in staking, understanding differences between varieties and which varieties tend to be more “fool proof” for first time gardeners.
Tomatoes can be thought of as having one of two growth habits: determinate and indeterminate.  Determinate tomatoes grow to a determined height and are not truly “vining”, but should still be staked for best results. Most tomatoes are indeterminate meaning that the stems, if given the opportunity (i.e. longer growing season), would grow to undetermined lengths.
In general, smaller tomatoes or “cherry-type” tomatoes (there are many varieties) seem easiest to grow. Because the actual tomato is smaller, it takes less time for it to ripen, which is great for our cool, short season. Also, with cherry-type tomatoes like SunGold (one of my favorites!), Sweet 100, Sweet Million, Grape, Green Grape and Yellow Pear you’ll get way more tomatoes per plant.
Many people seek heirloom varieties like Cherokee Purple, Brandywine, Mr. Stripey (another favorite!), Green Zebra, and Black Krim. You certainly get a lot of flavor for these varieties, but many fail to realize that heirloom tomato plants typically produce much fewer tomatoes per plant.They require a little more attention and watering, but you will be rewarded! Don’t give up if your first experience with heirloom tomatoes is not successful.
Good luck growing your own tomatoes this year!

Types of Tomatoes

Tomato Varieties
* Early Beefsteak – best large tomato for our climate
Early Cascade – one of the earliest to set fruit medium-sized; holds well on stem
* Early Girl – very early maturing; sets fruit at cooler temperatures
*! Oregon Spring – great for our cooler climate; good for sauces and ketchup
Santiam – great for cooler climates
Stupice – tolerates colder weather than most; very abundant and sweet
Ultra Girl – one of the earliest; harder to find these days

Grape – grape shaped tomatoes; very vigorous; very productive
! Black Grape – dark greenish black red grape/pear shaped; wonderful flavor
Green Grape – rounder than grape but maturing green’
* Patio – determinate; medium to small tomato; great for containers
* Red Cherry – classic, cherry sized tomato; a little later than Sweet 100 or Sweet Million
*! Sungold – VERY SWEET, low acid, orange cherry tomato; abundant harvest
* Sweet 100 – 1-inch super sweet cherry tomato; heavy yields; high in Vitamin C
* Sweet Million – slightly larger than Sweet 100; disease resistant; super sweet
Tiny Tim – determinate; small fruit on compact plant; great for containers
*! Yellow Pear – vigorous vines; abundant yields, roma-like consistency

Celebrity – semi-determinate; medium sized-fruit; disease and crack resistant
Legend – ”blight resistant,” developed in Oregon; does not perform well here
! Oregon Spring – great for our cooler climate; good for sauces and ketchup
*Patio – determinate; medium to small tomato; great for containers
Roma – THE paste tomato; heavy producer; usually determinate
Tiny Tim – determinate; small fruit on compact plant; great for containers

Black Krim – early maturing; dark red with shiny black/green tops; sweet
Brandywine – rosy-pink color classic tomato taste
* Early Beefsteak – best large tomato for our climate
! Lemon Boy – medium to large bright yellow tomato; very tasty; colorful in salads

Black Krim – early maturing; dark red with shiny black/green tops; sweet
Brandywine – rosy-pink color classic tomato taste
Cherokee Purple – medium sized; pink-purple with brownish color
! Green Zebra – small to medium sized green marbled tomatoes; unusually
smooth and mild flavor and texture
! Mr. Stripey – very low acid, tasty; very colorful tomato; not abundant like others
Yellow Brandywine – flattened golden yellow fruits

(* = good confidence builders for first-time tomato growers)
(! = My favorites)

This article was adapted from a piece of the same title in the Spring 2009 issue of The Social Gardener, the journal of the Whatcom Horticultural Society.
Chuck McClung has a Master’s Degree in Botany and assists others with their gardening dilemmas through landscape consultations, renovations, design assistance as well as gardening classes and workshops. He is the gardening columnist for the Foothills Gazette as well as a contributing author for The Social Gardener, the publication of the Whatcom Horticultural Society. He may be reached at

7 Comments to “Best Tomatoes: Tips for growing a NW favorite”

  1. Bill Bill says:

    Thank you Chuck, this was great advice.

  2. Norm says:

    Took a while to stumble on this; glad it is still here. I am forwarding it to a couple of new gardeners that want to grow some tomatoes.

    Thanks! Excellent piece.

  3. Heidi says:

    Thank you, we have been wanting to grow tomatoes for a few years, and this year we are going to do it. We don’t have a green-house, so we will have to get “starts” for this time.
    Hoping it all goes well here in Spanaway!

  4. Elena Harp says:

    Does anyone know where I can buy green grape tomato plants in Skagit or Whatcom county??
    Please let me know
    Thanks for any and all help.

  5. Susan Jenkins says:

    Great article, I am trying Heirloom cherry tomato’s for the first time this year and did not know they may not produce as much as regular type. Still looking forward to trying them out for flavor. I did Yellow Pear cherry tomatoes last year and had a bumper crop!!! Ended up with 11 pints of Green Tomato Salsa at the end of the year, YUMMY! I so appreciate all the great instruction!!

  6. Carol says:

    Thanks for the great information. . . I should have read this BEFORE I started!! but it’s good to learn whats going on with my tomato plants! Thanks! God bless.

  7. Lorraine says:

    I started my tub/container garden this year of 2017 and like many I found your site late in season. Really appreciate your making it all so simple and will look forward to next year. Unable to plant a regular garden as the gophers eat my plantings from roots up. THANK YOU SO MUCH.

Leave a Comment