Our Vegetable Inheritance

downloadAmong food and garden lovers alike, the current buzzword for value is heirloom, a very good description of open-pollinated vegetable seeds. Unlike hybrids, heirlooms can be saved year after year, and although we always think of the word as extending toward the past, it’s just as relevant to the future: heirlooms aren’t just what our great-grandparents grew, they are also the varieties we can leave to our great-grandchildren.

Heirlooms are most famous for offering great flavor and for enabling the gardener to “grow your own” from start to finish. But they offer a lot more than freedom from the need to buy seed every year.

Adaptability, for instance. Heirlooms are the special province of individuals and of small, regional seed companies, who do not need to sell zillions of packets in order to make a profit; and that means they tend to be better attuned to specific local conditions (drought in the Southwest, humidity in the Southeast, cold in the North) than “one size fits all” hybrids.

Hybrids are created through carefully controlled parentage, and as a result they are uniform. Every plant will be about the same size, and it will bear its fruit in the same narrow time frame. These characteristics are important to the mechanized operations of commercial growers, but they don’t do much for home gardeners.

And though hybrid varieties are often disease resistant, they are identically so. If a disease strikes that they cannot resist, every single plant will suffer.

Heirlooms, on the other hand, are individuals. Even when they are grown from seeds that came in the same packet, each plant is subtly different from every other. They grow and ripen unevenly, so you get a longer harvest period. And they are unevenly vulnerable to diseases. When trouble strikes, some plants will no doubt be afflicted, but others may come through.

All this is not to say there’s no place for hybrids, but hybrids are not in danger. It’s heirlooms that rely on home gardeners for their continued survival, heirlooms that offer independence, and heirlooms that give gardeners a chance to do their part for the preservation of genetic diversity.

To learn more, and to gain access to a huge assortment of delicious possibilities, consul the Garden Seed Inventory, available from Seed Savers Exchange, 3076 North Winn Road, Decorah, IA 52101; (563) 382-5990; It explains, eloquently, why heirlooms are important. And it is the source of sources, listing very nearly all the open-pollinated (nonhybrid) vegetable seeds available commercially in the United States, along with the names and addresses of the companies that supply them.

Within OCMGA, we have a dedicated group of members working with Seed Savers — watch this blog for an article about their efforts.


Organic Tree Fruits

For the home gardener, organic strawberries and bramble fruits are not much harder to grow than organic vegetables, but organic tree fruits are definitely a challenge. This is partly because plantings are in place for years — sometimes decades — which gives pests and diseases lots of time to dig in. It’s also because fruit trees have lots of enemies, many of them widely distributed and many of them extremely tough, thanks to years of natural selection in response to chemical biocides. Nevertheless, fruit trees can be grown organically if you are willing to take the following steps:

  1. Start by learning the basics. Never mind how delicious it sounds — is this something that does well in soil like yours, in your climate-zone, in your micro-climate? Are there particular cultivars that have built-in disease resistance?
  2. Pay close attention to the plants, keeping them in the best possible health. In addition to weeding, feeding, pruning, and applying the prophylactics (such as dormant oil sprays) that ward off problems before they happen, plan to spend plenty of time just watching out for trouble. Organically approved remedies work best when diseases are just getting started and pest populations are small.
  3. Keep it clean. Many pests and diseases winter over on fallen fruit, dead leaves, or weed debris close to the target plants, and a lot of the really nasty characters need to spend time on or in the ground in order to complete their life cycles. Rake up the fruit as soon as it falls and do the same thing for leaves, composting only healthy material (burn everything else, or send it to the landfill). Mow the area around the trees if it is in grass, plant a low cover crop such as vetch, or make sure the area is mulched.
  4. Accept imperfection, which is nature’s way. The goal is to have fruit that tastes good, not fruit that looks like it’s made of wax.
  5. Take the long view. Just as it takes years to build good soil with a fluffy texture, plentiful nutrients, and the necessary balance of life-supporting organisms, it also takes quite a while to establish the kind of self-policing ecosystem where beneficials are numerous enough to vanquish most pests. Until this happy state is achieved, there will be many temptations to resort to strong chemical fixes ‘in an emergency.’ If you succumb, you’ll lose some of the gains you’ve made in the journey toward balance, and the number of emergencies will not diminish as rapidly as it would otherwise.

Dealing with Deadly Drought

It feels like we haven’t had any significant amount of rain for over a month. The ground is hard, the grass is crackly, and all living things droop their heads in this heat. I could run up my water bill to shocking figures, or I could work with what I’ve saved in my rain barrel.

In times like these, it’s a good idea to keep your eye on the long term and give rationed water to the most important plants. Annual flowers and vegetables will be history by winter, no matter what, while expensive and slow-growing items like Japanese maples should be once-in-a-lifetime purchases.

It’s tempting to try to rescue the neediest; yellow-leaved plants with hanging heads are heart-wrenching, but plants already stunted by drought are the least likely to thrive later, even if they do survive. It’s better to water things that are OK but just a little peaked. And don’t forget that spring-flowering shrubs like lilacs start building next year’s blossoms as soon as they finish this year’s show. They need water to do it, so don’t let appearances deceive you into shortchanging them.


Smart watering using soaker lines to put the water right at the base of the plants

If possible, water whole areas rather than single plants. Dry soil wicks moisture away, so spots watered in isolation are surrounded by the enemy. Select the few healthiest tomatoes and peppers, give those all the water they need, and let the other vegetables go. Your crop will be smaller but better tasting (it takes a lot of water to make good fruit). If you’re determined to save annual flowers, shear them back. If rain comes, they will rapidly put on new growth and a burst of bloom.

And, remember, sprinklers are not the best way to water your plants. Water that lands on leaves is not absorbed. It evaporates before it reaches the ground, as does some of the water thrown into the air by a sprinkler. Watering the soil at the base of the plants really is more efficient. Even if there are no summer droughts to cause watering restrictions, it makes sense to conserve by watering effectively.

It is best not to water in the evening because leaves stay damp much longer, and damp leaves are a terrific breeding ground for many fungus diseases. The smartest gardeners water at dawn or in the early morning. With the whole day ahead, any water that does land on leaves has a chance to evaporate long before sunset.

Finally, let’s do away with the myth that water drops on foliage will burn the leaves in bright sunshine. Water droplets do magnify a bit, but not enough to even warm the leaves, let alone burn them.

July Gardening Tips

by OCMGA Master Gardener Vicki Schilleman

I had the pleasure of visiting the Minnesota Landscape Arboretum – University of Minnesota several years ago during a visit to Minneapolis. Located in Chaska, Minnesota, it’s a short drive from Minneapolis and well worth the trip. From the website: “The Minnesota Landscape Arboretum, a top visitor attraction, is more than 1,200 acres of gardens and tree collections, prairie and woods and miles of trails. As a premier northern garden, the Arboretum was borne out of the University of Minnesota Horticultural Research Center and established in 1958, with the Men’s Garden Club of Minneapolis, Lake Minnetonka Garden Club, Minnesota State Horticultural Society and other community supporters creating the Arboretum as a gift to the University of Minnesota.” 


Dahlia test garden

During my visit, I saw rosemary shrubs that were retained in the ground year-round (something I’ve not been able to duplicate even though we’re in the same climate zone). In another area, there was a huge garden of nothing but different types of dahlias that were being tested, and a kitchen garden with dozens of varieties of tomatoes. It’s also the only time I’ve ever seen a carrion flower.

Here are some gardening tips from the arboretum for the month of July:


UW-Extension Tips

We’re based in Wisconsin and can’t say enough good things about the expert help that is available to us through the University of Wisconsin – Extension. In a recent email to all Master Gardener members, there were two really good articles and I’m reproducing them here.

Expert’s Tip: 10 Tips for A Successful Tomato Container Garden

Ann Wied, Waukesha County UW-Extension Consumer Horticulture Educator

Not enough time or space for a garden?  Tomatoes grow great in containers. Here are a few tips to use yourself or share with others …

  1. Choose a compact, bush, or dwarf tomato variety. These tomatoes are often labeled at garden centers as “great for a container gardening”.
  2. Buy healthy, resistant varieties.  Choose varieties that are resistant to diseases prevalent to where you live.  Look for this information on the plant tag or garden catalog.
  3. Choose a container large enough to provide support for your tomato.
  4. Don’t rush to plant your tomato. Plant near the recommended planting date for your area. Even if you can protect the plants from frost and/or cold night air, cool temperatures can keep growth slow, cause nutrient deficiencies, and prevent fruit set. In addition, once fruits start to form, cold temperatures can cause the tomatoes to become deformed.
  5. Place the container in an area that has at least 4 hours of direct sunlight each day.
  6. Water your tomato plant whenever the top 2 to 3 inches of soil is dry. This may be every day or every other day if the weather is hot and dry.
  7. When you water, water until it drains through the bottom of the pot and don’t let the plant sit in excess water.
  8. Fertilize once a month throughout the growing season with a fertilizer labeled for vegetable plants.
  9. If the tomato gets too large or bushy, support it with a small cage or stake and/or prune out some branches.
  10. Monitor for disease and insect problems. If a disease occurs, remove and destroy infected leaves or the entire plant if the disease is severe.


Click here for a version (pdf) you can print and hand out to clients!

Expert’s Tip #2: Tips on preventing seed production when hand-pulling garlic mustard plants

Mark Renz; Associate Professor and Extension Specialist; University of Wisconsin-Madison

Ever wondered about these questions:


  • Is there a developmental stage where garlic mustard plants can create viable seed if pulled?
  • How does different disposal methods impact seed production?


I have summarized the results of research done on this topic (read the reference for all the details and their specific conclusions):

What stages can garlic mustard produce viable seeds when hand-pulled?

Plants were hand-pulled over three consecutive week sand separated into three phenological groups:

  1. flowering: < 5% of flowers developing into fruit
  2. early-fruiting: 40%-60%of flowers developing into fruit
  3. late-fruiting: > 95% flowers developing into fruit

Of these stages only the flowering stage didn’t produce any viable seed or seedlings the following year. While lots of variability existed with the later two stages, each of these produced viable seeds. Although this experiment was conducted atone site in one year other studies using phenology have found consistent results from year to year and site to site. Thus this is clear evidence to me that the flowering stage is a safe timing to not worry about seed production if plants are hand-pulled.

What is the best method to dispose of hand-pulled garlic mustard plants?

Three disposal treatments were evaluated where plants were left in field conditions for three weeks:

  1. left in a pile on the ground
  2. scattered on the ground
  3. hung over tree limbs

Results found that regardless of disposal method, similar viable seed and seedlings the following year were found. While these results are encouraging, they were conducted over one year in one location in Ohio. I would caution about over-interpreting this information as different environmental/physical conditions may alter the result.

Can second-year garlic mustard plants resprout from taproots if just shoots are removed?

Plants were cut at the soil surface at one of four phenological stages:

  1. budding: no flowers
  2. flowering: < 5% of flowers developing into fruit
  3. early-fruiting: 40%-60%of flowers developing into fruit
  4. late-fruiting: > 95% flowers developing into fruit

While some plant stages resprouted quickly from the first three timings (bud, flowering and early fruiting) no resprouting occurred with the late late-fruiting timing. Regardless of timing, all treatments did not result in the production of viable seed and plants did not survive the following year. Thus stage of shoot removal doesn’t appear to be that important, and while resprouting can occur it may not produce any viable seed. Similar to above I would caution about over-interpreting this information as lack of shoot resprouting could have been the result of site specific factors.

The big picture:

In summary, this research confirms that viable seed production can occur if hand-pulled after the flowering stage. If you are hand-pulling after this timeframe it is recommended to plan on some of the seeds being viable. Realize that while zero seed production is the goal, all treatments had large reductions in the production of viable seed (largest # of viable seeds per plant was < 20).

Consideration of the level of infestation should be included in the decision making process as well as this information. If hand-pulling plants in an area recently infested with few plants and limited to no garlic mustard seed bank I would recommend not taking any chances and bagging/removing plants if past the flowering stage. However, if the location has been infested for multiple years, a seed bank is likely present and I would be more willing to leave plants after flowering on site. A few additional viable seed won’t be the end of the world as repeated trips for multiple years will be needed regardless of the success in any one particular year.   


Chapman, JI, Cantino PD and McCarthy BC. 2012. Seed Production in Garlic Mustard (Alliaria petiolata) Prevented by Some Methods of Manual Removal. Natural Areas Journal Jul 2012 :Vol. 32, Issue 3, pg(s) 305-315.

Flowering and Fruiting Issues in Solanaceous and Cucurbit Crops

by Lisa Johnson, horticulture educator for Dane County UW-Extension

GettyImages-107981379-584ba6b35f9b58a8cd1bc980Often, this time of year, I get calls from gardeners asking why some vegetables are not fruiting. Unpredictable spring and summer weather temperatures can adversely affect crops, especially tomato, pepper, and eggplant in the Solanaceae family, and winter squash, cucumbers, pumpkins, melons, and summer squash in the Cucurbitaceae family. These plants rely on a certain range of temperatures to initiate flowers, bring them to maturity, and produce fruit. Fruit production can be affected any time during this process.

Temperatures at night have the greatest impact. If temperatures are too hot or too cold for even a few days during flowering, plants may abort flowers or fruits. For solanaceous plants, daytime temperatures above 85 F for several days, nighttime temperatures above 70 F, or nighttime temperatures below 55 F cause fruit to abort. If you think back to 2012, which had high daytime and nighttime temperatures, low fruit production is understandable. In fact, temperatures over 104 F for four hours can cause tomato flowers to abort.

Temperatures and Pollination

tomatbbee2018wTomatoes, peppers, and eggplants are self-pollinating, but cucurbit flowers must receive multiple pollinator visits for complete pollination to occur. Squash, for example, requires an average of 12 visits by a pollinator to set fruit. And it has to happen fast. Pumpkin and squash flowers open at temperatures above 50 F; cucumber and watermelon, above 60 F; and muskmelon above 65 F. But these flowers only stay open and viable for a day in the case of watermelons, muskmelons, and cucumbers, and half a day or less for other cucurbits.

Also, all cucurbits are not alike. Some plants have separate male and female flowers, or female flowers only, or have perfect flowers, with male and female parts in the same flower. If they have separate male and female flowers, usually male flowers open first. Early in the season, more male flowers are open than female flowers, but you need both to produce fruit! As the plant ages, the proportion of female flowers increases. Cucurbits are affected by other factors that influence whether a flower will be male or female. Cool temperatures promote female flowers in cucumber, squash, and pumpkin. Conversely, high temperatures promote male flowers and delay female flower development. In pumpkins, temperatures of 90 F during the day and 70 F at night lead to abortion of female flower buds.

Light levels also affect flower development in cucurbits. High light levels promote female flowers; shade can reduce those numbers. The bottom line is that a lot can happen between flowering and fruiting!

Designing Tall

Want some color and height at the back of your flower garden, but not interested in shrubs? There are many tall flowers that can anchor the back of a border. Which ones you choose will depend on the space available (some of them are as wide as they are tall) and on your growing conditions.

Foxgloves, for instance, will grow to 6 feet if they’re in moist, nearly neutral soil in semi-shade, but they might top out a bit below 4 feet if they’re in average soil in the sun. The same goes for black snakeroot (Cimicifuga racemosa), which might stretch to 7 feet or more if happy and dwindle utterly if not.

Foxgloves are usually columnar, their tall flower spikes rising almost leafless from a broad rosette at the bottom. Snakeroot is rangier; sending out beautifully cut-edged leaves almost all the way up the stem. Meadow rue (Thalictrum spp.) also sends out leaves all the way up, but they, like the flowers, are lacy and delicate, so the overall effect is light. T. rochebrunianum, which has purple blooms, and T. speciosissimum, (aka T. flavum ssp. glaucum), which has pale yellow flowers and bluish leaves, are both 4 to 6 feet tall. White-flowered T. polygamum can grow to 8 feet.


Joe Pye weed (tall and purple) in my garden

Other tall flowers include delphinium, Caroline lupine (Thermopsis caroliniana), plume poppy (Macleaya cordata), Ligularia spp., Japanese meadowsweet (Filipendula purpurea), foxtail lily (Eremurus stenophyllus), Joe Pye weed (Eupatorium purpureum), and globe thistle (Echinops bannaticus). Read cultural descriptions carefully before you buy; many of these plants have very specific needs and some — especially plume poppy and Joe Pye weed — are very aggressive spreaders.