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TheWaterbug
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"Planking" carrot seeds to increase germination?

I've never successfully grown carrots before, but I want to try again. One tip I read about on the Infallible Internet (tm) is to "plank" the seeds by covering them with a wooden board:

https://youtu.be/mwuvb89HF0o?t=855

Anyone have an opinion on this?

I just tried this on Tuesday. We'll see if it works:

Image

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applestar
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Jal_ut who has not been posting in a while but was a long time posting member here has often advocated this method.

I tried with just cardboard earlier in the summer and it seemed to work great. :D

I removed the cardboard after 4 days which is what I remembered James recommending.

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TheWaterbug
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Thanks! Good to hear!

At the same time I put another ~20 seeds between wet paper towels in a Ziploc on my counter so I monitor those without having to pull up the board every day. Because otherwise I would be pulling up the board every day!

As you might guess, I am a terrible fisherman . . .

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Gary350
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I have used boards before to make several types of seeds germinate. Trick is to remove board at the correct time other wise you get a long skinny stem with 2 leaves that often dies. Check every morning & evening. I have best luck with 1/2 long carrots. Sometimes I plant carrot seeds in beds 3'x4' and sometimes wide rows 1' x 10'. We are in a drought almost no rain in 3 months the board trick won't work for me this year I guess I just wait for rain. Carrots do good here growing all winter it never gets cold enough to kill carrot plants. I like to sprinkle seeds on soil then sprinkle 1/4" soil over seeds they will not germinate unless we have lots of rain and wet soil for a month. My carrots take 3 to 4 weeks to germinate. My best carrot crop has always been toss seeds out in the snow about Feb carrots come up grow and ready to harvest about June. Be sure to make a place to plant carrot seeds ahead of time so it is ready to plant seeds in Feb.

imafan26
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Thanks for the post. I have never tried this method before. I have not had problems germinating and getting carrots to grow. I just have problems getting them and most root crops to develop roots in my home garden. I need to figure out how to prepare the bed to reduce the nitrogen so I don't get giant tops with small roots. The carrots grow better in my alkaline plots but it is hard to grow carrots here since it is over 80 degrees for most of the year and carrots will get woody and bitter in a short time. The carrots did flower well this year. I kept the carrots in the ground from December to July. The carrots were of a decent size but still had some forking, and Nelson carrots retained some sweetness but they were still on the hard and bitter side after being in the ground so long and in the heat.

I am not particular about planting anything in rows. I just broadcast the seeds on top. I am bad about thinning though.

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digitS'
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I had problems with the "out of sight, out of mind" board technique, WaterBug. Carrot seed often takes a long time to sprout, especially in cool soil. By the time that happened, I'd be neglecting to check them and then pulling the board off - they fried in the sunlight!

Pelleted carrot seed is dang near fool-proof :wink: ... That protective coating holds moisture.

Another technique that worked just fine for me is called “fluid seeding.” Here is North Carolina Extension talking about it: "... fluid seeding where seeds are sown in a protective gel. Blend 2 tablespoons of cornstarch into a cup of warm water, then let cool. Add seeds or pre-sprouted seeds to the gel. Put the seed gel in a plastic bag and cut the corner off so you can squeeze the gel into rows or holes in the garden soil." I used hot water but be sure that it all cools before adding seed.

I tried this with lettuce seed also but lettuce is quick compared to carrots. I had lettuce seedlings even on the soil surface where a few drops of the gel dripped by accident.

Steve

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TheWaterbug
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digitS' wrote:I had problems with the "out of sight, out of mind" board technique, WaterBug. Carrot seed often takes a long time to sprout, especially in cool soil. By the time that happened, I'd be neglecting to check them and then pulling the board off - they fried in the sunlight!

Pelleted carrot seed is dang near fool-proof :wink: ... That protective coating holds moisture.

Another technique that worked just fine for me is called “fluid seeding.” Here is North Carolina Extension talking about it: "... fluid seeding where seeds are sown in a protective gel. Blend 2 tablespoons of cornstarch into a cup of warm water, then let cool. Add seeds or pre-sprouted seeds to the gel. Put the seed gel in a plastic bag and cut the corner off so you can squeeze the gel into rows or holes in the garden soil." I used hot water but be sure that it all cools before adding seed.

I tried this with lettuce seed also but lettuce is quick compared to carrots. I had lettuce seedlings even on the soil surface where a few drops of the gel dripped by accident.

Steve
Thanks! I only sowed about 6' of 30' along that raised row, so I have room to try 4 different methods if I want. I intend to sow 6' of seed every ~week or so, both to spread out my harvest (I hope!) and to see when's the optimal time to plant around here.

Corn starch gel is fun! I'll have to try this for my next section. So no plank for gel seeding?

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digitS'
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No plank.

:)

Steve

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TheWaterbug
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digitS' wrote:No plank.
Thanks! But I assume that you cover with a thin layer of soil, correct?

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TheWaterbug
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So here are the results of my first "plank" test:

I sowed seeds under the plank on the morning of 9/24. That evening I remembered to do the paper towel test, so those were "sown" about 12 hours later.

On the evening of 9/30 I saw this on my kitchen counter. They'd been under something, so there was little/no light reaching them, so as to simulate the conditions under the plank:

Image

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I went down to the garden and took the plank off of my carrot bed, and saw some similar, leggy seedlings. I gave them a misting of water:

Image

The two broad-leafed things at the top are weeds. :evil:

But the rest look like leggy carrot seedlings. Or at least they look like the same things that were in my Ziploc bag.

I didn't get a chance to see them this morning, but I'll look tonight and tomorrow morning. It shouldn't be too hot today (71 F), so I'm hoping they won't cook, and will have a a few days to harden before it gets warmer (supposedly 79 next week).

I probably should have taken off the plank at least 1 day earlier, and maybe 2 days earlier. The seeds in the baggie were 12 hours behind the seeds in the ground. I should have put the seeds in the bag the night before the seeds in the ground, so they'd be telling me what was coming, instead of what had already happened.

So maybe for the next 6' of seeds I'll do some planked, some not planked, and some in corn starch gel. For science!

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So what's going on here, with planking? Two things. Firstly, having a board over the top seals in moisture, and prevents the row from drying out. But laying plastic over the top isn't enough. Second (and probably most important), having a plank over the row compresses the soil, and ensures good contact between the seeds and the soil. That's very important for many seeds, which NEED soil contact to get enough moisture to germinate. Same is true with beets. Other seeds are happy to germinate just by being sealed up in a humid hole.

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That’s interesting about beets — and presumably Swiss chard. The ones I stepped on after sowing sprouted fine (but they got eaten by something so I only have 3 ragged seedlings with 2 sets of true leaves left). This might explain my difficulty with trying to start transplants in loose potting mix.

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I have excellent and quick germination when laying wetted cardboard over top of my cover crop, the key is to keep the cardboard moist.
Wood is probably better because cardboard can dry out quicker possibly wicking away moisture?

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TheWaterbug
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I took a look at the seedlings last night, and they're fine. But I forgot to take photos. And then I forgot to look this morning.

But I definitely got better germination where the plank made solid contact with the soil. Where it was just covering the soil, but not making firm contact, I got less germination.

So I'll really press it down next time.

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applestar
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Yeah when I did it, the seedlings HAD NOT YET SPROUTED when I removed the cardboard after 4 days but then they started to come up pretty thickly a little later.

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TheWaterbug
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TheWaterbug wrote:So here are the results of my first "plank" test:

I sowed seeds under the plank on the morning of 9/24. That evening I remembered to do the paper towel test, so those were "sown" about 12 hours later.
Well, here's what happens 4 months later!

Image
Image
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Image

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digitS'
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Yay! It WORKED!

Thanks for doing the follow-up.

Obviously, zone Sunset 23/USDA 11a ... :> You will have to think of other creative things to do with those carrots :wink:

We have had a very warm January, with some recent rain and lots of wind right now. There is very little snow left in the neighborhood yards. Nearby, the family built a snowman a couple of weeks ago. There is almost nothing left of it except for their carrot.

:) Steve

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applestar
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Very nice! I can’t get carrots to grow that big/mature because they would either freeze in the winter or get eaten up by pests in the summer (wireworms, voles, etc.)

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Gary350
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I tried to grow carrots many times but never got big carrots like yours in 4 months it take me March to Dec to get carrots 1/2 as big as yours. .

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TheWaterbug
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I'm not sure what part of this is right or wrong, but here's what I did:
  1. This was the onion/leek bed during the Spring and Summer. Originally prepped with manure, and drip-fertilized until harvest.
  2. After I pulled the leeks, onions, and a million weeds, I tilled it thoroughly, but did not add any manure or other amendments.
  3. I raked the tilled soil up into raised rows and flattened the tops of the rows. The rows were probably ~6" above the troughs, as you can see my original post. I did a better job in later plantings of leveling the tops so the planks would make better contact.
  4. I planked the seeds for 5-6 days. 4 would have been better, as the seedlings would have been less leggy.
  5. I thinned after 2-3 weeks.
  6. Plenty of water via my 1/4" Drip-a-long drip tubing, but no fertilizer.

imafan26
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It is an interesting idea. I just scatter the seeds. Planking may not work as well for me. Snails love to hide under things like planks. However, I can modify this idea and use paper towels instead, since that is something I do when I plant small seeds in compots.

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PraticalGardener
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Interesting, I didn't know about 'planking' carrot seeds. My guess is if you remove the boards after they sprout, then they will be ok. You just don't want them on for too long or else it acts like a heavy mulch and smother them from sunlight, just like a very thick mulch. :roll:

Imafan, I did eventually figure out 'my knack' for starting carrots outdoors, by using paper towels. It took me several years figuring out what mistakes not to do in the meantime. :roll: What eventually succeeded for me was to take a paper towel, peel it apart to one layer (one ply), sprinkle the seeds on top of the pre-loosened ground, lay the paper towel directly on top of the carrot seeds, and weigh the paper down with small rocks to prevent the wind from blowing them around. Then just keep the paper towels moist, watering them roughly every other day.
One-ply paper towel was thin enough to not smother out all my carrot seedlings, and would decay just after the 'perfect timing', but I could peel the paper towels off abit sooner if I wanted to. :)

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Gary350
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What was your day time & night time temperatures when you planted seeds in the garden?

What was your day & night time temperatures when you harvested carrots 4 months later?

What type soil do you have?

After you germinated seeds in the house are those the same seeds you planted in your garden?

Are you growing hot weather or cold weather carrots?

Are you using high potassium fertilizer?

What is your seed spacing when planting them?

Did you use irrigation the whole 4 months while growing carrots?

I am determined to learn best way to grow carrots this year. I want to grow 100 lbs of carrots in 4 months. What is the average weight of a carrot?

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I have done paper towels before in pots. I sprinkle the seeds on top of the moist media cover with paper towel (I did not separate the plies), and kept it moist. About 4-5 days later I would check for germination and once most of the seeds have started to come up, I would peel off the paper towel and bottom water until the seedlings are well established It works well for green onions and cilantro. Otherwise, I tended to move the seeds around too much when watering the benches overhead.

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I have success with carrots by planting them on raised beds and put a sheet of burlap over them and keep it moist. The carrots should be up within about a week

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I don't plant a lot of carrots since they don't do all that well in my garden and I only have a small window to plant them. I do have carrots in my garden now that are ready to be harvested. I only broadcast the carrots the temperature here must be less than 75 degrees in the daytime (November-April). My soil is deep and soft enough. It is in a raised bed with 10+ inches of compost enriched oxisol (clay). Down side, it is also very rich in nitrogen. I have to starve the soil more to get the carrots to grow more roots and less tops. I did broad cast the seed in January. The roots have only been getting larger in the last 3 weeks or so. A month ago I had baby carrots about 3 inches long. Since it is now close of 80 degrees the carrots are bitter and sweet at the same time. Still they did better than the onions which were sweet but only about 2.5 inches in diameter. I lost a lot of the garlic and they only averaged 3 cloves. They would have done better in my alkaline plots. I have had bigger carrots there where the nitrogen levels are lower.



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