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GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published February 7, 2016

From time to time I have written about the All-America Selections (AAS). These are new flower and vegetable varieties that have been judged by AAS to be the best performing new varieties for home gardeners. All-America Selections is an independent non-profit organization with the mission of “promoting new garden varieties with superior performance judged in impartial trials in North America.”

When gardeners start ordering seeds or plants they may see a variety that is “new and improved” or “better tasting,” but they have no way of knowing the truth of these claims. However, if a new variety is a national All America Selection (AAS) they can be assured that it is likely to perform well in their garden and offer something new or different than similar varieties currently available. In fact, not only must an AAS selection perform well in trials around North America, it must also “have at least two significantly improved qualities” over current varieties to be considered for selection.

While in the past flowers seemed to be the main focus of AAS selections, vegetables have been front and center in recent years. I suspect that is because many seed companies have been putting their energy into developing new and improved veggie varieties, the current focus of many home gardeners.

Let’s take a look at some of the new veggies winning the AAS designation for 2016. Since tomatoes are everyone’s favorites, I will begin with the two tomatoes that won the AAS award for this year. First is ‘Chef’s Choice Green F1.’ This is a modern hybrid that looks like an heirloom with large (9-10 oz.) beef-steak type fruit.

The fruit of Chef’s Choice Green F1 are very pretty with green and yellow-striping. The flesh has a sweet, citrusy taste and good texture. Existing varieties that it resembles are Aunt Ruby’s Green, an heirloom, and Fried Green F1. Other desirable characteristics of Chef’s Choice Green F1 include its “well-behaved” 5′ foot tall indeterminate vines and resistance to numerous diseases. Seed for this tomato can be purchased from Totally Tomatoes at

On the other end of the spectrum of fruit size is Candyland Red, a currant-type tomato with small .5″ red fruit. These little fruit are very sweet and richly flavored. Candyland Red resembles Sweet Pea and Matt’s Wild Cherry tomatoes but differs from other currant-type tomatoes because its growth is not as rampant, plus the fruit forms on the outside of the plant, making harvesting the tiny gems easier. While more compact in habit than similar varieties, these plants still grow 6-8′ tall and should be spaced 3′ apart with staking provided for support. Seed of Candyland Red is also available from Totally Tomatoes.

Other AAS 2016 vegetable selections include:
Pepitas F1 is a beautiful yellow-orange medium-sized pumpkin with green stripes, making it useful for fall decorating. In addition, its flesh can be baked and the naked or hulless seeds (pepitas) can be roasted and eaten. (Available in 2017.)

Prizm is a short kale (10-24″ tall) with bright green ruffled, curly leaves. The almost stemless leaves are tender with good flavor. The plants quickly re-leaf after harvesting. This kale is compact enough to be grown in containers and raised-beds. Remember kale is a cool-season plant and should be started early in the season. (Available in 2017.)

Look for these and the other 2016 and previous years’ AAS selections when buying your garden seed. They are varieties that should do well in your garden because they are “Tested Nationally and Proven Locally®,” All-America Selection’s tagline.

Photos from All America Selections are available at:

Ripening Green Tomatoes

GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written October 2, 2015

Frost is coming and it is likely to be soon. The average date of the first killing fall frost in our area is October 15, but earlier for cooler spots. Before that happens and perhaps even a little earlier, gardeners should start picking mature green tomatoes. As we discussed last week, some types of mature fruit will ripen after picking. Tomatoes are one of them.

Our tendency as gardeners is to leave tomatoes on the vine in the fall until frost threatens and then quickly pick everything we can find that has some color. Some gardeners cover their vines with clear plastic to make a sort of greenhouse to keep the plants and fruit warmer during the day and protect them from frost at night.

However, covering plants with plastic or blankets is not going to help much because the fruit is injured by cool night temperatures below 50 degrees. Exposure to repeated chilly nights will damage the fruit, resulting in more fruit loss from decay. Once night temperatures start dropping below 40 degrees the damage is even greater.

The good news is that mature green tomatoes will ripen very well off the vine and still provide you with the wonderful flavor of homegrown vine-ripened tomatoes. There is no need to pick smaller green tomatoes that have no chance of ripening. Only pick mature green tomatoes. Telling the difference is a little tricky, but not hard. Generally, the fruit should be at least three-quarters the mature size expected for the variety. They will have turned from a bright green to a lighter green or whitish color. They do not need to have started turning red or the expected mature color yet.

Once the fruit are harvested, take them indoors and prepare them for ripening. This is done by first washing them with cool clean water and then allowing them to air dry completely. If any are cracked or split, they are more likely to rot before ripening so throw them out or use them in a recipe that calls for green tomatoes.

After roguing out the damaged tomatoes, you may want to sort those you have left. The ones that have developed a tinge of color will ripen first. Put these in one group, and then sort by “greenness.” The next step for many gardeners varies depending on just how many tomatoes they have and their capacity for storage. I recommend placing them in single layers in covered cardboard boxes. (Leave a little space between tomatoes.) Some folks wrap each fruit with newspaper and then place them in a box, but this is tedious and makes it difficult to check for both ripe or rotten fruit.

Tomatoes are the type of fruit that will ripen after picking and produce ethylene gas as they ripen. Exposure to ethylene gas from another source will speed up the process. If you are in a hurry for ripe tomatoes, place some of your green ones in a closed bag with some ripe bananas or tomatoes because they produce ethylene gas.

Our mothers and grandmothers placed their green tomatoes on the windowsill thinking that exposure to light was needed for ripening. Actually, they need the warmth not the light from the windowsill. Tomatoes will take about two weeks to ripen when kept at a temperature around 65 to 70 degrees. Cooler temperatures, but above 50 degrees, will result in slower ripening.

A chills is in the air so start harvesting your green tomatoes for ripening. Now is the time for action!

The Dilemma of Determining Fruit Maturity and Ripeness

GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written September 27, 2015

Gardeners are often faced with the dilemma of knowing when to harvest their fruits and vegetables. When is the right time to pick them and will they ripen afterwards? At the risk of revealing that I am a botany nerd, technically fruit are the protective female organs of flowering plants that contain their “babies” or seeds. The protective fruit may be fleshy structures like apples or dry structures like nuts. Apples, peaches, grapes, tomatoes, peppers, and melons are all examples of fleshy fruit.
Physiologically, fruit are mature when their seeds are fully developed. However, if you have ever encountered a humongous fully mature zucchini you will know that the desirable stage for harvesting and eating this “fruit” is when they are much smaller with tender skin and undeveloped seeds. As consumers, there are some vegetable fruits that we prefer to eat when they are immature, like summer squash, and others when fully mature, like melons. When it comes to tree fruit like apples or peaches, we usually find the fruit much tastier when fully mature and ripe.
Ripening is also a physiological process. It involves changes in the fruit, such as the flesh becoming softer and sweeter and the skin changing from one color (often green) to another. A variety of chemical changes can occur during ripening, including the breakdown of starches into sugars leading to a sweeter flavor. Softening results from a change of insoluble pectin in the cell walls to soluble pectin. The acid content of the flesh also decreases as the fruit ripen.
Now back to the original question of when to pick fruit and if they will ripen off the plant. The answer is some do and some do not. Because of this, horticulturists divide fruit into two groups. The group that do not ripen after picking tend to produce only small quantities of ethylene gas as they ripen. Ethylene is an odorless naturally occurring hydrocarbon gas. It is sometimes referred to as a plant aging hormone. Fruit that do not ripen after picking include cherries, grapes, raspberries, strawberries, other berries, watermelon, and citrus fruits. These are picked when fully mature and ripe.
The second group are fruit that produce greater amounts of ethylene as they ripen and do ripen after picking. These include apples, pears, peaches, nectarines, apricots, plums, cantaloupes, bananas, and tomatoes. These fruit should be harvested at the “right” stage of ripeness after becoming fully mature. I am sometimes asked how to determine when to pick homegrown apples. It is tricky as the timing is based on the color of the skin, how easy it is to detach from the tree, flavor, and softness.
Commercial fruit growers have equipment for testing skin color, amounts of sugar, and flesh firmness. Gardeners should periodically check for sweetness by tasting the fruit. The flesh will be starchy if it is not ripe. Gardeners can also use their noses to check the fruits’ aroma and their eyes to judge skin color. Apples change in firmness from rock hard to slightly softer flesh that gives just a bit with a press of the thumb. Ripe apples should separate from the tree fairly easily with a slight upward twist. A gardener must sacrifice a few fruit to determine the “right” time, but it is better than harvesting an entire crop of unripe or over-ripe fruit.
Now that fall is here, I suspect frost is not far off, so next week we will tackle picking winter squash and green tomatoes.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written August 30, 2015


Having been at this job for over 30 years, I have seen gardening trends come and go. Way back in the 1980s there were numerous local gardeners interested in food gardening, growing both vegetables and tree fruit in their backyards. You could always find a large variety of vegetable transplants available at big box stores, as well as at local nurseries.

In the 1990s things started to change, fewer and fewer gardeners were interested in growing their own produceThe big box stores changed to offering fewer vegetable transplants, instead focusing primarily on colorful annual flowersI am not sure if this happened because gardeners realized that gardens and fruit tree were a lot of work, they had easy access to fresh produce from local farmers markets, their busy lives did not allow much time for gardening, or a combination of all these.

I am happy to say we have now come full circle and gardeners, especially younger gardeners under the age of 50, are interested in food gardening againThe focus is on veggies and herbsA survey taken by Today’s Garden Center indicates that these “youngsters” say gardening gives them a sense of accomplishment, allows them to become more self sufficient and have more control over the safety of their food, and provides a way to get children outside and teach them about nature. Wonderful!

Another thing to know about younger gardeners is their interest in food and cookingThere is a proliferation of television cooking shows that are enjoyed by both young adults and older folks like meBecause the All-America Selections (AAS) organization has noticed that cooking fresh foods is “trending,” they plan to market their 2016 winning herb and vegetable selections with five videos that demonstrate cooking techniques.

With the home garden focus back on vegetables, many of the big seed companies are strongly marketing their new vegetable varieties, especially ones with more compact growth habits that are easier to fit into the smaller gardens of today’s gardeners. These are a few that have already hit the market or will be arriving next year:

Basil ‘Docle Fresca’( is an AAS 2015 winner that is a “new and better” compact Genovese basil plant with sweet tender leaves and growing only 10 to 14 inches tallIt is drought tolerant and a good container plant

Pea ‘Masterpiece’ ( a pea that Burpee calls a “triple treat” with edible tendrils, pods, and peasGrowing up to 30 inches tall and 32 inches wide, these pretty peas plants work well in containers and limited-space gardens

Kale ‘Simply Salad Kale Storm’ (, is a mix of salad kales that are slow to boltThe seed combined into single pellets is a mix of different leaf textures and colorsNot only will this work well as fall cool-season crop for container growing, it will also serve as an attractive ornamental during the fall months

Tomato Heirloom Marriage Series (PanAmerican Seed) is a series of tomato hybrids that are the results of crosses between two heirloom varieties to create an F1 hybrid variety, “marrying” the best characteristics of each parent for improved performance in the gardenOne already available (along with others) is ‘Big Brandy’ whose parents are ‘Big Dwarf’ and ‘Brandywine’ Coming in 2016 is ‘Marzinera’, a cross between ‘San Marzano’(my new favorite tomato) and ‘Cream Sausage.’

Zucchini ‘Brice’ (no retail seller available ) is a zucchini that produces 3 to 4 inch light green round fruit on compact plants with attractive mottled leavesIt is more manageable than many zucchini and is great for container or limited-space gardeningThe fruit can be hollowed out for stuffingYummy!

This season isn’t even over yet and I am thinking about next year. Whoa!


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written July 30, 2015


We had a brief respite from the hot weather this past week, but now it is back. I am hoping that my garden tomatoes will have set more fruit during the cooler weather. I have been able to start harvesting a few ripe tomatoes, but alas many of these tomatoes are cracked.

Cracked Tomatoes: After a long wait for ripe tomatoes, it is disappointing that many have radial cracks or splits in the skin starting at the stem. This occurs because the flesh of the fruit grows faster than the skin. Temperatures over 90 degrees or temperatures fluctuating widely between day and night can lead to cracking. It also can be attributed to heavy pruning when staking tomatoes. This exposes the fruit to light and increases the temperature of the fruit.

Uneven watering, fluctuating between very dry to very wet soil, can also give rise to tomato cracks. Heavy nitrogen fertilization causes very fast vine growth, also causing more fruit to crack.

Finally, some varieties are more prone to cracking. A number of the heirloom varieties, like Brandywine, are notorious for their tendency to crack. That is one of the reasons why modern hybrids were developed. For example, Burpee developed their hybrid Brandy Boy to have the same great taste of Brandywine without the problems, including cracking, associated with growing this heirloom.

The problem with cracked tomatoes is that the cracks in the skin make it easy for secondary fungi and bacteria to infect the fruit. The appearance of mold, extremely soft fruit, or liquid leaking from the tomato are sure signs of infection. Discard them. You can eat cracked fruit that are not infected, but do so quickly because they will not last long.

Blossom Drop: Astute veggie gardeners have noted the lack of beans on their bean plants and attributed it to the heat. When temperatures climb well above 90 degrees, beans and peas will drop their flowers without setting fruit. The same often happens with tomatoes and peppers too. The reason for “blossom drop” and the lack of fruit involves pollination and the subsequent fertilization of the embryo in the ovary within the flower.

You might think the reason for this is that bees are not active in the garden when temperatures are above 100 degrees, but beans, peas, tomatoes, and peppers are self-pollinating and thus do not depend on bees or other insects to enable pollination and fertilization. However, these self-pollinating flowers do need wind or insects to shake the pollen from a male part of the flower (anther) onto a female part of the flower (stigma).

What about the veggies that do require an assist from bees and other pollinating insects? Fruit production of cucumbers, melons, and squash seems to slow in hot weather too. Aborted or misshapen fruit are because bees are not very active in the hot weather and because pollen does not remain viable for very long.

We can not do anything about the hot weather, but we can reduce plant stress and minimize cracking and blossom drop by keeping the garden soil evenly moist, mulching to cool the soil and conserve moisture, and not applying excessive amounts of nitrogen fertilizer. It’s also a good idea to provide bees with some moisture. Turn a bird bath or large pot saucer into a bee bath by filling it with coarse gravel or river rock and adding water. The stones are used as perches, so the bees will drown in the open water.

Tomato Transplants and Planting

GARDEN TIPS – written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA April 23, 2015

Here I go again talking about tomatoes, but since they are the favorite veggie crop of home gardeners I am hoping you will forgive me. This time, let’s talk about tomato transplants and how to plant them.

Horticulturists will tell you when purchasing tomato transplants select ones that are only six to eight inches tall with a strong main stem (about the same diameter as a pencil). Avoid plants that are leggy, yellowish-green, much too big for their pots, already flowering, or infested with insects. Also, avoid plants that have grown too large in the greenhouse and been cut back to disguise this.

A healthy, stocky transplant is the ideal, but many gardeners who grow their own transplants from seed end up with leggy plants. This is because the plants were either started too early, not provided with enough light, or both!

Leggy tomato stems are weak and often can not support the top of the plant, especially in windy weather. To remedy the situation, gardeners should bury the stem and the roots when planting. This is best accomplished by creating a shallow 4 to 5 inch deep trench, removing the leaves from the bottom 2/3 of the stem, laying the transplant on its side in the trench, and then covering the roots and stem with soil. Leave the remaining leaves several sets of leaves above the soil.

Roots will form along the buried stem, resulting in a stronger plant. The leaves and stems left above the soil will naturally turn and start growing upwards. Before planting, remove the pot including peat or other biodegradable pots, and gently then loosen the roots.

When purchased at the nursery, transplants have usually already been “hardened-off” by exposure to wind and sunlight and by receiving less water and fertilizer than they were getting in a greenhouse. To get them ready for the “real world,” homegrown transplants started indoors will need to be hardened-off  by gradually introducing them to outdoor conditions. This is done by placing them outdoors in the sun for couple of hours and then increasing the amount of time outdoors each day for about a week, but bringing them indoors at night.

Tomatoes are frost-sensitive, warm season plants. They prefer warm weather and warm soils. There is no advantage to planting them early and protecting them from frosty nights. If you are into easy gardening with no extra work, plant your tomatoes no earlier than May 1st, the average date of our last spring frost for most of the region. However, tomato plants will not grow much until the soil warms to at least 600 F and prevailing daytime temperatures are above 700 and nighttime temperatures are above 600.

If you yearn to plant your tomatoes early, you can create a “mini-solar greenhouse” for each with Wall-of-Water or Kozy Coat garden teepees. Garden teepees are 12″ diameter cylindrical garden devices made of channeled clear or tinted plastic sheeting. The channels are filled with water and then the teepee is set over a plant. The water absorbs heat during the day, keeping the plant warmer than the surrounding air during the night and day and helping warm the soil.

When teepees are tilted inwards at the top of the cylinder early in the season, they can provide considerable protection from frost, down to 160 F according to the manufacturer. They also protect plants from wind. Teepees should be removed when temperatures reach 80 to 85 degrees, otherwise they “cook” the plants.

May 1st is just a week away so start getting ready for planting tomatoes, but wait until the soil and temperatures are warm enough.


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 2/7/14

For the past several years I have been trying different types of tomato cages for supporting my tomatoes, but these efforts have usually ended in failure. Last year windy weather resulted in all my cages and plants blowing over. What a disaster! Since I am obviously not an expert on staking tomatoes, I have been researching where I went wrong.

Tomato plants are a vine. When not provided with some type of structure for support, they will grow along the ground. If left to sprawl like this, an indeterminate tomato variety can take up as much as 16 square feet of garden area. That=s a lot of space for just one tomato plant. Plus, many of the fruit that develop touch the ground, increasing the potential of fruit rot.

Gardeners can maximize garden space and minimize fruit rot by providing tomato vines with support and growing them upright. Before we discuss caging, staking, and trellising, let=s talk about the difference between determinate and indeterminate tomatoes.

Determinate tomatoes are varieties with bushier, more restrained growth. Vines are shorter, growing from 3 to 4 feet in length. The main vines develop numerous branches which stop growing when the plants begin to flower. With all the flowers and fruit developing at the same time, commercial tomato growers favor determinant tomatoes for processing. The varieties, Celebrity, Oregon Spring, Bush Early Girl, and Rutgers are popular determinate garden tomato varieties. Many early season tomatoes are determinate varieties.

Indeterminate tomatoes are varieties with vines that keep growing and growing until frost kills them in the fall. Their vines can grow from 6 to 12 feet in length or longer. They flower and fruit over a period of two months or more. While indeterminate varieties typically develop mature fruit later in the season, they tend to produce more tomatoes over the entire season. Many of the heirloom varieties popular with gardeners today have an indeterminate growth habit.

So where did I go wrong? I used tomato cages, the 3-4

types, commonly sold to gardeners. These cages will work fairly well for caging determinant tomatoes. As noted earlier, determinate tomatoes are more compact and most only reach a height of three or four feet.

The indeterminate tomato varieties that I have been growing are much too big for these short cages. They require taller, more substantial support in the form of a tall wire cage, sturdy trellis, or strong stake, especially when you live in a region like ours that sometimes experiences strong summer winds.

Indeterminate tomatoes can be Acaged@ by constructing a 2

diameter cylinder type cage with 5

hog wire (the type used for reinforcing concrete) or using a heavy gauge wire cattle fencing panel to make a square cage with 18″ wide sides. The cage must be anchored to the ground in some way, especially in windy areas, such placing a length of rebar inside the cage and pounding it a foot or more into the ground. Place cages three to four feet apart in the garden.

You may want to consider making your own cages like these for growing indeterminate tomatoes. Caged tomatoes are unpruned (less work) and tend to yield more fruit per vine than staked tomatoes, but the fruit is smaller. Next week I will finish up this ATomatoes@ series with information on staking and trellising tomatoes.

Published: 2/7/2014 1:56 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 2/14/14

When warm weather arrives in early summer, our garden tomatoes will start to grow very fast. Once a plant is a foot or so tall, it will start to branch. As rapid growth continues, the plant flops over and grows along the ground unless it is provided with support. Left to grow horizontally, the vine will develop more and more branches, eventually becoming a tangled mess.

As noted last week, sturdy tomato cages are usually adequate support for shorter determinate tomatoes, but the taller indeterminate types need more support. This can be provided by staking each plant individually or building a trellis.

Staking individual plants involves pounding a sturdy 6-8 foot stake firmly into the ground three to four inches away from the plant. To avoid injuring the roots, do this within two weeks of planting in the garden and before branching begins.

When the vine is a foot tall, tie it to the stake using a soft tying material that won=t cut into the stem, such as strips of nylon pantyhose, or use one of the commercial tying materials available at garden stores.

After this, pinch out any side shoots or Asuckers.@ These side shoots develop between the base of a leaf and the main stem. A tomato plant staked and Apruned@ in this way produces fewer tomatoes per vine, but the fruit that does develop will be larger. However, it makes the fruit more prone to blossom end rot and sunburn. You can try to avoid these problems by also leaving the first sucker that starts to grow above the first flower cluster that develops. Any other suckers or shoots are removed, leaving two main shoots.

If you are a gardener who grows more than a few tomato plants, consider building a trellis for support. The ABasket Weave@ or AFlorida Weave@ is commonly used to trellis commercially grown tomatoes. Using this system space, your plants 18 to 24 inches apart and then place 6 to 7 foot stakes between every plant or every three plants. Use strong posts, such as a metal T or a 4×4 inch wooden fence post, at the ends of the row.

When plants are a foot tall, it=s time to start Astringing@ the trellis using non-stretching twine, such as baler=s twine, or wire. Secure the twine or wire to the end post and then run it on one side of the tomatoes and fix it to the next stake. (Hint: Twine can be fixed by wrapping it around the stake.) Keeping the Astring@ taught, continue running it to the second stake on the opposite side of the tomatoes and fixing it to the next stake. Continue weaving the Astring@ in this manner until you get to the end post, fasten it to the post, then return the Astring@ to the beginning post by weaving it back on the opposite sides of the tomatoes, and finally fastening it to the post. Repeat the process every time the plants grow eight to ten inches.

So that you don=t have dense, overcrowded vines, prune your trellised tomatoes. Leave two shoots per plant if they are spaced two feet apart and three shoots if spaced three feet apart. Many gardeners often use their own variation of the ABasket Weave@ or design ingenious other trellises that work for them. The key to success is building a trellis that=s tall enough and sturdy enough to support the vines. I think I=ll try trellising my tomatoes this year.

Published: 2/14/2014 1:51 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 1/31/14

New garden catalogs are arriving daily, telling me that it is time to start planning this year’s garden. Spring must be around the corner!

Of course tomatoes are at the top on my list of veggies to grow. There is nothing like a home grown tomato fresh from the garden. If you plan to grow your own veggie transplants, now is when you ought to be ordering your seeds and getting ready to plant. Tomato seeds should be planted about six weeks before the anticipated date of planting outdoors in the garden.

When perusing seed catalogs you might notice that modern hybrid varieties, like Burpee’s Better Boy or Big Boy, are not as popular as they once were. Today’s gardeners are clamoring for heirloom varieties because of their full flavor and attractive fruit of various colors and shapes. Specialty mail-order seed companies and even mainstream companies are offering an expanding list of heirloom tomatoes.

Modern hybrid tomato varieties were bred primarily for commercial field production. Breeders sought firm, uniform, deep red fruit and resistance to soil pathogens. They did not focus on flavor. As a result, some of the flavor we desire in a fresh tomato was lost during their development.

Heirloom tomatoes are older varieties that have been passed from one generation to another. Unlike modern hybrid tomatoes, heirlooms are open pollinated. The prime reason for the “growing” interest in heirlooms is their flavor. Many folks feel that heirlooms have more of the robust tomato taste they want in a tomato.

Specialty mail-order seed companies that specialize in tomatoes are a good place to look for tomato varieties to grow. Totally Tomatoes ( is offering a new series of tomatoes called the “Wild Boar Series” that are new introductions from a small organic farmer and breeder. The series is the result crosses he made from his favorites among hundreds of heirlooms and hybrids and selecting the resulting crosses for their extreme flavor, interesting appearance, and coloring.

Tomato Growers Supply Co, ( offers over 500 varieties of heirloom and hybrid tomatoes, peppers, and eggplants. Tomato Fest ( only offers organically grown heirloom tomatoes with a list of a 600 varieties including paste, dwarf, determinant, heart-shaped, and of course red, orange, yellow, green, striped, brown, purple, and even blue varieties.

Many seed companies, even the big name seed catalogs (like Burpee), are offering grafted tomatoes for sale. A grafted tomato is one that has been fused together via the propagation method of grafting. This involves placing a desirable variety (scion) on top the roots of a different variety (rootstock). The scion grows into the upper part of the plant and produces fruit of the desirable variety. The rootstock grows into the root system and imparts that variety’s characteristics to the roots.

While heirlooms may have better tasting fruit, the plants lack resistance to certain soil pathogens bred into most modern hybrids. Grafted tomatoes allows tomato growers to grow tasty heirloom tomatoes on rootstock that is resistant to certain soil diseases. Many of these rootstocks also improve plant vigor and productivity.

So do not procrastinate, decide what to you want to grow and order your seed or grafted plants now.

Published: 1/31/2014 1:40 PM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 5/10/2013

Now that warm weather has arrived, veggie gardeners are getting ready to plant their tomatoes. When you are out shopping for tomato plants, you may notice some pricey tomato plants labeled as grafted tomatoes. Last summer, I wrote about grafted tomatoes and their impending arrival this spring. Their recent appearance at garden centers, nurseries, and even big box warehouse stores, is prompting me to answer some questions you might have about them.

What is a grafted tomato? A grafted tomato plant is one where the top of one variety of tomato has been attached to the roots of another variety of tomato. This horticultural technique is called grafting. The top variety is the ‘scion’ and the bottom variety is the ‘rootstock.’ Special rootstock varieties have been developed with certain characteristics, such as resistance to soil-borne diseases and nematodes. Some rootstocks may also increase plant vigor and production or provide better tolerance of soil that’s too wet or dry.

What are the advantages of grafted tomatoes? University trials indicate that it’s possible to realize a 50 per cent or more increase in production with grafted tomatoes. Last year in their Demonstration Garden, Benton Franklin Master Gardeners planted two varieties of grafted tomatoes side by side with two of the same varieties that had not been grafted. By the end of the season the grafted plants were bigger and appeared more productive than the same non-grafted varieties.

Better production is wonderful, but the greatest value of grafted tomatoes for home gardeners is their use with heirloom varieties. Most heirloom tomato varieties aren’t resistant to troublesome soil-borne diseases. Grafting the heirloom scions onto specific rootstocks that are resistant to these diseases can be the difference between getting delicious fruit by the end of the season or having a dead plant. However, grafting onto any rootstock will not provide the same benefits. The rootstock must be resistant to the soil-borne diseases of the area to reap the benefits.

Is growing a grafted tomato any different than growing one that’s not grafted? Growing grafted and non-grafted tomatoes is basically the same, but how they are planted is significantly different. Grafted transplants should never be planted deeply with the roots and stem buried up to the first set of leaves. The graft must be above the soil line, not below, to realize the benefits of the rootstock.

Look at the stem of a grafted transplant and you should be able to see a line where the two varieties were joined together. Take note, this is a fragile union. Handle the grafted transplant gently. When transplanting, support both the roots and the stem, being careful not to pull on the scion stem. After you water the plant to settle the soil, make sure the graft is still above the soil line.

Note: Because the graft union is especially fragile when the plants are young, don’t transplant on a windy day. If your area is prone to wind, provide the plant protection from the wind. If your grafted transplant comes with a plastic or silicone clip at the graft union, remove it two to three weeks after planting.

Because your grafted plants may grow to be larger and more vigorous than non-grafted plants, be sure to provide the vines with sturdy support in the form of cages or staking. During the growing season remove any sprouts from the rootstock that may develop below the graft.

I successfully grafted a tomato plant on my own and will be giving that a try in my garden. I’ll let you know how it grows.

Published: 5/10/2013 2:05 PM

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