Category Archives: Radish

Biennials: Readying Radishes and Turnips To Replant

A week and a half I ago,  my overwintered brassica roots came out of the cold room for inspection.  Let’s look at

  • Storage conditions
  • Roots that stored best
  • Roots that stored less than perfect
  • Curing roots before planting.

Storage conditions

These roots were harvested last September. I selected the best individuals to bear seed. The roots were stored in our cold room. During the summer,  an evaporator and compressor keep the cold room around 4C. During the winter we use a little heater to keep the room from freezing.

The roots are stored in plastic bags with holes. This maintains good humidity levels for the roots. I always identify root bags that are for seed.

And I also add ‘for seed’ labels. This keeps important roots out of winter salads and snacks.

Some Roots Look Great: Black Radishes & Turnips

A bit of sprouting.

And some rooting.

These turnips want to get planted.

Some Roots Need Some Work: Watermelon Radishes

I’ve had more of a problem getting these guys through the winter. Last year I planted out a bunch of roots but within a month they’d all rotted in the field.

So this year I took more time to inspect the roots.

Many of these radishes have rotten taproot tips.

I trimmed the rotten portions from the taproot.

Other radishes have blemishes on the actual roots. I consider composting these radishes but I also want to plant out as many roots as possible so …

I cut off the rotten portion of the root.

In some radishes the rot runs a little deep. These root were not saved.

Radishes post surgery. These gaping wounds will be let to cure before planting them in the ground.

I use a sharp knife to operate on these radishes. I disinfect the blade after each root with rubbing alcohol in a spray bottle. This minimizes spreading disease.


Now I let the roots sit at ambient temperatures for a week or so.

They are placed in clean flats with a lot of space for air circulation.

This should help wounds cure and might make the transition from cold room to ground smoother.

I’ve since planted the roots. Now I wait …

In the meantime, you can always read some of my other turnip and radish seed posts.


Special Seed Winnowing Bucket

On my last post, Xander commented on the bucket I was using to winnow radish seed. The bucket in question in one of the 2011 additions  to my seed cleaning arsenal. Here a few shots of this bucket in action:

Restricting seed and chaff flow rate

I use this modified bucket to restrict the amount of material falling at once and pour a steady stream of material in front of the winnowing fans.

I used an old wooden field marker as the bar and fixed it in place with duct tape. This works better on a bucket with straight sides.

Usually the material flows easily through the gap. Sometimes the chaff gets stuck and blocks the flow.

Increasing flow rate

I use a finger to dislodge any stuck material.

Decreasing flow rate

If on the other hand material is going through too quickly, I use my hand to hold some of the chaff back. I might also do this if the chaff threatens to pour over the bar instead of under!

Anybody have any equally handy high-tech seed cleaning equipment?

Also, happy new year!

Saving Radish Seed With Gusto!

As a new seed saver I used to work delicately with seed crops to avoid any damage and minimize seed loss. This worked well for plants like arugula that have seed that shatters easily and light chaff. But radishes, with their big spongy pods that squished before shattering and left pieces of pod the same size as the seed, gave me a headache. And after a couple miserable attempts, I gave up on radishes for many years.

Four years ago, with some seed saving experience, I tried radishes again with success. The differences in my approach came down to making sure the pods were very dry and not being too delicate with the extraction process (quite the opposite in fact!).

I clean  radish seeds with multiple cycles of threshing, screening and winnow steps in my radish cleaning. This is what I call aggressive seed cleaning and use this approach with seeds that don’t easily shatter (snap beans, and now chicory, fall in this list).

This post covers the radish seed cleaning,  you can read about growing the plants for seed here:

On with the cleaning!

Primary Threshing

We harvest the plants when they’ve dried down in the field. Then let them dry further in the barn

When they are dry, I put the plants in a bin and stomp them with my boots.

I screen out the plant stems and largest material with a 1/2″ screen.

This is what fell through the screen. There are still a lot of whole pods in here.

I run this through a 1/4″ screen. The whole pods stay on top.

This is the chaff and seed (with a few whole pods) that went through the second screen. I leave this in a bin and pay attention to the pods that didn’t fall through.

secondary Threshing

This is what didn’t go through the screen.

I stomp on the pods some more and then screen again the 1/4″ screen. I add what falls through the screen to the bin with what fell through during the previous step. I repeat with any pods that didn’t fall through the mesh.

After a few passes all the plant material has fallen through the 1/4″ screen and is collected in one bin.

I take this bin into the barn.


I transfer the chaff and seed to a bucket and then winnow.

I start with the fans on low-speed and crank the speed each successive pass till I achieve desired results. In the case of radish seed both fans are at high-speed.

I winnow over three bins on a tarp. I can recuperate my seeds if I have a fanning mishap, and also I can see what is being separated at different steps.

The left bin (closest to the fan) is full of seed and non-shattered pods. The bin on the right is full of stems and shattered pods.


Repeat Threshing And Winnowing

I compost the plant matter from the bin on the right and screen the bin on the left with my 1/4″ screen. crushing anything that doesn’t go through with my boots.

After another cycle or two of screening and winnowing, the large plant matter has been removed from the seed.

Only the seeds remain with a few big bits. At this point I take out my specialized radish screen.

Final Screening

This is one of my fine collection of colanders, the square  holes are the right size for radish seed.

I pour the seed into the colander and delicately shake from side to side …

separating the last bits from the seed lot.

I lay the clean seeds on a tray to dry a few more days than bag them up to bring them into the office.

Key Lessons

As you can see I really kick the seeds out of those pods – hence aggressive seed cleaning. Getting the seeds free from the pods is the critical first step in seed cleaning. From that point on screens and fans can do the rest.

Next, I’ll talk about how aggressive winnowing does the job for lettuce seed.

Winter and Spring Radishes

Though I haven’t posted much lately, we have been keeping busy.

Here are some pictures of this year’s radish seed production.


Winter radishes are big generally spicy radishes that are grown in the fall for winter storage.

This purple radish is a F1 cross of a Red Meat radish (also called watermelon radish) with a black Nero Tondo radish. It was seeded around August 1 2010, harvested in the fall, and stored in the cold room through the winter.

This spring I sorted the stored radishes and composted any that hadn’t stored well.

On May 4th, I replanted the radishes in one row on 18″ spacing. First I laid them out then I buried them. (The orange roots in the picture beyond the purple radishes are golden beets.)

I left the leaves above ground to start photosynthesizing.

June 10th, the radishes had gone to flower. Currently they have set a number of seed pods.


Spring radishes are what most people think of as radishes – small and round or red and long with a little white tip. They’re usually ready in 28 days or so from seeding. They can be seeded throughout the growing season though spring seeded radishes tend to be the mildest.

These radishes were seeded at the end of March in our greenhouse.

I removed most of the leaves from each radish but left the leaves at the growing point intact. Andrea Berry from Hope seeds suggested I do this.

Last year I had just snapped the leaves off but found the radishes took awhile to start putting leaves out when I replanted them.  Andrea thinks leaving the middle leaves on the radish speeds up new leaf growth.

I bagged up the radishes and tossed them in the cold room for a bit. I labelled the bag with date they went in the cold room and the fact that they are for seed production (not for a delicious snack with a little mayo.)

I usually then leave them in the cold for 1-2 weeks to simulate overwintering.

This year the abundant rain delayed a lot of my seed planting. I only took the radishes out of the cold room on June 1st.

I then planted them in the field in two rows per bed. Last year I planted my spring radishes 18″ apart in the row  but I found that the plants weren’t very big. This year I reduced the inrow spacing to 12″.

I made sure not to bury the leaves.

Last week the radishes had definitely caught and were starting to bolt.

I think that Andrea’s leaf snapping advice did speed up new leaf growth. Will that offset the extra two weeks I left the roots in the cold room? We’ll just have to see.


With this post I’ll try to get back into a more regular blogging routine. I hope all your fields have recovered from one seems like heavy rains from coast to coast.

Plant Seed Crops on Time – Seed Production Planning Part 4

This is the fourth part of a series on crop planning for seed production. Seed production planning part 3 covered calculating how much to grow to meet your farm and marketing demands.

The next step is choosing when to plant your seed crop to get a reliable seed harvest. (Most of this article was originally posted on its own last spring but I thought it fit nicely into this Crop Planning discussion.)


My first seed harvests were from vegetables that bolted and didn’t make it to market. This worked well for a bit, and then it didn’t . I learned that if you want a reliable seed harvest, the crop has to go into the ground with that goal in mind. This means planting at the right time.

When you plant a seed crop too late, you run the risk

– The crop simply won’t have time to set seed before fall showers, hard frosts and then snow compromise harvest opportunities and seed quality.

– Or the crop might return to vegetative growth as the day-length gets shorter. In mid-August, I’ve been caught with little seed when kale and some lettuces  quit producing flowers, stop maturing seeds and begin to sprout new leaves.


This depends on how well a crop tolerates cold and frost. Here are three ways to divide crops:

– The hardiest crops can be seeded as soon as the ground can be worked. This includes lettuce, peas, dill, cilantro, fava beans, overwintered roots (carrots, beets, rutabaga, onions)

– Hardy crops (but a little less hardy than the hardiest) occasionally bolt after sudden spring cold snaps. It is usually safe to seed these crops by early May directly in the field. You can plant these crops a bit earlier if you use row cover for cold protection or  plant hardened off transplants instead of seeds. This category is mainly filled with annual brassicas like  short season broccoli and cauliflower and leafy greens like arugula, tatsoi, and  mustards.

– Frost sensitive crops need to wait till after the last frost. Waiting a week or two longer, until the  soil warms up, will create better conditions for these crop to establish. But don’t plant so late the crop won’t have time to mature before fall frosts! Row cover and plastic mulch can speed up soil warming. Nightshades (tomatoes, peppers, and eggplants), Cucurbits (squash, cucumbers, and melons), and beans are the main frost sensitive crops.


Planting any seed crop in less than ideal conditions will reveal which plants and varieties can better tolerate adversity. Recurring selection under these conditions will make the crop hardier. If you walk this road, though, be prepared to lose some crop as you learn.

And of course not all crop and varieties will be successful on all sites or in all climates.

This year’s wet weather has delayed a lot of our spring plantings. Many of our earliest seed crops have been planted a couple of weeks later than I would like. I’ll keep you posted on how that affects our seed harvests this season.

Shortly I’ll wrap up this seed production planning series with a post on crop rotation.

Seed Production Planning Part 3 – How Much To Grow

This is the third part of a series on crop planning for seed production. Seed production planning part 2 covered calculating how much seed to harvest to meet your farm and marketing demands.

The next step is determining how many plants you need to grow to produce the amount of seed you need. We’ll look at the basic math to calculate how much to plant and two examples.


This is the basic equation:

Harvest Targets x Safety Factor ÷ Yield = Bed Length to Plant

Harvest Targets: This was calculated in Seed Production Planning part 2.

Safety Factors: Weather, pests, diseases, and weeds can dramatically alter what you can expect to harvest. Seed yields are more variable than vegetable yields. It’s good to target growing 25% to 75% more seed than you need to compensate for the potential losses.

Yield: The amount of seed you can expect to harvest on average from a certain number of plants or area of crop. Last spring I wrote a blog on seed yields that goes further into the subject.

Here is an updated chart of some of our seed yields at Tourne-Sol farm.

Crop Rows/Bed Inrow spacing grams/bedft*
Beans bush – 2 pole – 1 6″-12″ 75-100g
Beets/Chard 2 12″ 100g
Brassicas 2 or 3 12″-18″ 25-100g
Cucurbits 1 24″ 25-100g
Lettuce** 3 12″ 10-28g
Onions 3 12″ 25-50g
Peas bush – 2 pole – 1 6″ 50-75g
Solanacea 1 or 2 12″-24″ 3-10g

* A bedft is a one foot long slice of your growing bed.

** Our lettuce yields are lower than what is possible in drier climates.


In Seed Production Planning part 2 we estimated 6720g of Tatsoi seed would meet our hypothetical farm and marketing needs. From previous experience I know my Tatsoi seed yields about 50g/bedft but that the yield can vary greatly from year to year.

Harvest Targets x Safety Factor ÷ Yield = Bed Length to Plant

6720g x 1,5 ÷ 50g/bedft = 201 bedft

If I grow 200 bedft, I should be able to meet my Tatsoi seed needs. If the weather cooperates and I harvest before much seed shatters, I could potentially harvest much more seed than I need.


Harvest Targets: 321g would meet our hypothetical farm and marketing seed needs.

Yield: I usually get about 7g/bedft of seed from small to medium-sized tomatoes like Jaune Flammée.

SF: On our farm tomato yields don’t vary as much as brassica greens. I’ll only use a 1.25 SF.

321g x 1,25 ÷ 7g/bedft = 57 bedft

I should meet my Jaune Flammée seed needs if I grow 60 bedft of plants.


In my next post, I’ll tackle when to plant seed crops to make sure you can harvest on time. And later, I’ll cover some seed crop rotation basics.

I also plan on posting some of what we’ve been doing during this rainy spring.

Hope it’s as sunny as you would like it to be wherever your skies are …

Radishes Blooming and Pruning Lettuce

Last week, I received a few e-mails about growing radish seed. Here are a few radishy answers for those questions. Also, I have been pruning lettuce leaves to increase ventilation.

Radish Seed

These radishes have begun to bloom. These are grown 2 rows/bed with 18″ in-row spacing. They seem to be smaller plants than some other radishes I’ve grown out. They might still bulk up, but I wonder if I could have planted them tighter.

I grow spring radishes (as opposed to winter storage radishes) as annuals:

  • We seed them densely and harvest a few weeks later.
  • Emily (Tourne-Sol radish buncher extraordinaire) selects those she likes by their for roots, stems and so forth. The rest go to market.
  • I haven’t tried this but Greta has told me to then put the roots in a bucket full of water and discard the floaters (too pithy!).
  • I top the chosen radishes and stash them in the fridge for 7-10 days. This simulates overwintering and gets the radishes to bolt at the same time.
  • I then transplant the radish stecklings (roots) to the field.

To successfully grow radishes as annuals for seed, I have discovered they need to be started as early as possible.  I found that when I seeded in early that after fridge time and stecklings getting established in the ground, the radishes only bolt in late July – doesn’t leave much time for plants to flower and set seed before fall rain.

This year we seeded radishes in a tunnel  in late March to get an additional month of seed growing potential.

You can read more about radishes in Principles and Practices  of Organic Radish Seed Production from  the Organic Seed Alliance. (Dowload the document free from their website.)

Pruning Lettuce

The lettuce plants I transplanted at the beginning of April are turning into leafy monsters. I went in on Monday and took off the outer leaves to let the air in. My continuous fear with lettuce is that it suddenly turns to jelly.

Red Iceberg lettuce. The two first rows have been cleaned up. Compare with the lettuce jungle in the back rows.

As I do this, I rogue out any slimy specimens.

I try to handle lettuce on a sunny windy day so the exposed plant stems can dry and heal before submitted to more damp overcast weather.

All this pruning creates a lot of leafy biomass.

Luckily, I have a few helpers who love to process such tender biomass.