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Jodi Lew-Smith, Ph.D.
High Mowing Organic Seeds
Recipe for Growing High Quality Seed
What will I talk about today?• OVERVIEW OF SEED QUALITY – what it
means and how to evaluate your own
• OVERVIEW OF GENETIC PURITY – a separate but equal topic with respect to seed quality
• SPECIFICS on seed production in the Northeast (this is where the pictures come in – so be patient!)
WHAT DO WE MEAN BY QUALITY SEED?
• Germinates at or above a defined minimum germination – usually 85% for vegetable seed, 75% for flowers and herbs
• Germinates:– quickly – with strong vigor – a full set of seedling parts
A quirky and KEY note about seed quality
The HIGHER the initial germination rate (i.e. quality), the LONGER the seed will stay viable
IT’S DIRECTLY PROPORTIONAL!
[And follows, the lower the quality, the more quickly it dies…]
BASIC RECIPE FOR “GOOD SEED”
• Strong fertility• Good air flow and disease
control• Fully mature at harvest =
“finished”• Harvested as quickly as possible• Dried as quickly as possible to
~13% moisture or lower• Not allowed to get too hot (>85-
90°) during drying• Stored in cool, dry conditions
once dry
SAMPLE TESTS FOR FRESH CROPS – DO THEM IN YOUR
KITCHEN!
COUNT CAREFULLY!
Evaluating your kitchen germ test
• Anything over 80% is great for a “dirty germ”• Anything above 50-60% is considered
potentially viable, especially if there is chance of dormancy and/or immature seed to remove
• The lower the percent, the more cleaning it will require
• Below 50-60%, you can try to clean the seed to saleable, but it’s a risk that the labor will be wasted and a sure thing that the seed will never be high quality
CONSIDERATIONS FOR GENETIC PURITY
=ISOLATION ISOLATION ISOLATION
ISOLATION DISTANCES• CUCURBITS and other insect-pollinated
crops: MINIMUM OF .5 miles between crops, but ideally more like a whole mile (size of crop is a factor)
• CORN and other wind-pollinated crops: 1000 feet between two relatively similar crops, at least 2 miles from GMO
• PEPPERS: 5% outcrossing requires 5-600 ft• TOMATOES: ~1% outcrossing requires 25-
100 ft (more for potato-leaf types)• BEANS, PEAS, LETTUCE and other full
inbreeders: no isolation required
What if I’m not sure?
• DISCUSS with your seed company
• Have you or your seed company do a GROWOUT of 50-100 plants to look for off-types
NOTE: OFF-TYPES are a big problem for seed companies because they’re not caught until seed is grown by customers. They result in recalls!
OK WE’RE GETTING TO THE PICTURES NOW…
SEED PRODUCTION IN THE NORTHEAST: Wet-seeded crops
1.CUCURBITS = “vine crops” = Squashes, melons, cucumbers
• easy to grow• Spaced 1-ft for melons, cukes, summer
squash• Spaced 2-ft for all longer-vined crops• need plastic and row cover to get
enough heat for some of them• seed quality reliable • yields highly variable
CUCURBIT HARVEST CONSIDERATIONS
= WAIT AS LONG AS POSSIBLE AND HARVEST BEFORE ROT (OR RIGHT AROUND FROST)
• MOST SQUASHES WILL CONTINUE TO MATURE SEED IF HARVESTED AND STORED
• SOME LONGER-SEASON SQUASHES WILL REQUIRE ‘CURING’ IN THE NORTHEAST
WINDROWS ARE HELPFUL
WET SEED EXTRACTOR
SEED COMING OUT OF DRUM
Transferring Seed
Washing Seed
Seed drying in Greenhouse
Seed FractionsINITIAL CLEANING
2. TOMATOES
• plant as early as possible in MAY to get decent seed yields – needs long days during flowering
• Spacing usually 18 in.• Usu. require plastic and spray to grow
well• cherry types always yield better• quality usually good with good handling• requires fermentation and defuzzing
SEED PRODUCTION IN THE NORTHEAST: Wet-seeded crops
TOMATO HARVEST CONSIDERATIONS
• HARVEST MULTIPLE TIMES AS FRUIT RIPENS
• CAN HARVEST PARTIALLY RIPE AND ALLOW TO RIPEN FURTHER UNDER COVER
• FERMENTATION CRITICAL FOR REMOVING GEL COAT AND REDUCING DISEASE
• RINSE MULTIPLE TIMES
3. PEPPERS and EGGPLANTS
- Spacing usually 12 inches- Usually need plastic and row cover – we
use raised hoops (i.e. low tunnels)- problems with TPB- Fruit can be harvested partially ripe- May not have enough heat to mature
seed for all but earliest varieties of bell peppers and eggplants
SEED PRODUCTION IN THE NORTHEAST: Wet-seeded crops
PEPPER AND EGGPLANT HARVEST CONSIDERATIONS• Peppers need to be fully colored but can do
this out of the field and still mature seed
• Need to avoid rot that easily discolors seed
• Need to rinse super well to get off flesh that sticks to seed
• Need to work quickly once removed from fruit as seed discolors and loses quality if left sitting wet
1. SHORT SEASON CROPS WITH PODS
– Brassica rapa = bok choy, mizuna, tat soi, other mild greens
– Brassica juncea = most all the spicy mustards– Brassica oleracea = sprouting broccolis, other
quick-growing oleraceas, mostly Asian types– A few flower species like Cleome, Nicotiana,
Sweet William
• Spacing ranges from 4” to 12” depending on size of plant frame
• We transplant them all
SEED PRODUCTION IN THE NORTHEAST: Dry-seeded crops
PODDED SEED HARVEST CONSIDERATIONS
• We use a ballpark figure of 70% brown as the time to cut the crop. Earlier and there’s a lot of immature seed, later and it shatters too much
• Important to get it out of the field in the northeast. (out west they cure in the field)
• Needs to be as dry as possible before threshing
• Once threshed you can screen out most of the chaff before beginning to winnow with fans
Staked Tat Soi crop 2005
CUT AND WINNOWED
BROUGHT IN FROM FIELD TO DRY
DRYING
THRESHING – YES, with a pickup
WINNOWING
REASONABLY CLEAN SEED
2. CORN
• Flint corn is very easy• Popcorn is feasible, but more
commercial varieties can be very late to mature
• Sweet corn is feasible, but requires harvesting while still wet and being dried under high heat to stop fungal progression
SEED PRODUCTION IN THE NORTHEAST: Dry-seeded crops
DRYING TAKES A LOT OF SPACE
CORN SHELLER
Corn seed typically germs well and comes out pretty clean – moldy seeds need hand-picking
FINISH CLEANING FOR ALL CROPS TAKES PLACE IN A SEED
MILL
WHAT MAKES SEED PRODUCTION WORK FOR
PEOPLE?• Foremost is a passion and dedication to
growing seed.
• Seed growers typically don’t see profits for several years, so having a dedication to sticking it out through the learning years is key.
• For brand-new seed growers, our recommendation is to take a few years “practicing” by growing small test crops to see how you like it and which crops work better than others
What does and doesn’t work?
• In our experience, it rarely works well to grow commercial seed as a sideline to commercial vegetables. While it works fine to save your own seed on a vegetable operation, the higher standards for commercial quality seed makes it nearly impossible to give the seed crops the attention they need while simultaneously managing the intense needs of a vegetable operation.
• Said another way, letting things go to seed under a regime of benign neglect on a vegetable farm very rarely yields commercial quality seed.
• Likewise, it does not work well to grow a crop for both fresh direct-market sales and also for seed, as the temptation to harvest the best of the crop for fresh market and leave the remainder for seed is too tempting. This is the opposite of what we want, as we want the BEST of the crop for seed.
What does and doesn’t work?
• It CAN work well to combine seed production with other farming ventures that have more similar cycles and equipment. An example is grains, which are likewise harvested once at the end of a long season.
• One nice thing about seed crops is that seed – if good quality and well-stored – will keep for several years and can be sold over a long window.
• For a small grower with limited isolations for seed, the ability to
grow a large crop of one seed type each year and sell it over several years may make it feasible to do “off the shelf” sales, which is something seed companies always appreciate.
• Storage for seed does not need to be fancy – it just requires getting the seed clean and dry and keeping it that way in a relatively cool place. (Rubbermaid tubs in a cool cellar can work)
One way to break into seed growing:
• Select varieties for your test productions that one or more of your target seed companies already sell and try to grow these.
• Before you do so, take a look at the price points and do some calculating to see if you can think you can grow it for a price that’s roughly half of the retail price – as this is typically close to the wholesale price.
• For very common varieties, the going wholesale price can be quite low because the larger organic seed wholesalers grow huge productions that benefit from economy of scale.
• Once you have some seed, get in touch with the seed buyer and let him or her know about it as a “backup” to their regular supply. If the price at which you’re offering it isn’t very different from what they’re already paying, they might be willing to purchase some.
A second means to break into seed growing
• If you have a nice crop of a variety that a seed company doesn’t sell, the typical process is to get in touch with the trials manager and provide a sample of the seed.
• If it does well in trials and you are willing to continue growing it, the company may well want to add it to the catalog and buy it from you.
• Seed companies are looking for reliable supplies of anything they add, so one-time overages are rarely of interest to them.
• If you’re willing to commit to a variety, a seed company is more willing to work with you
Recent new seed production method using unheated high
tunnels• Allows BIENNIAL seed production in the
Northeast• Tunnels provide protection on either end of
the season, plus optimizes flowering time • Opens up possibilities for local organic
breeding in a whole new set of crops• Opens up possibilities for a new niche crop in
seasonal high tunnels – either as rotation or with intercropping
• Allows us to grow seed we could never before grow in New England
First commercial cabbage seed crop in Vermont for at least
100 yrsAPRIL 2013
Same crop JUNE 2013
Copenhagen Cabbage June 16, 2013
Final yield = 20 lbs at 83% germ before cleaning
Consider using your hoophouse for a rotation that looks like
this!
THANK YOU!