A different seed starting technique - "Dense Planting

[applestar]

I was surfing around the other day and came cross a seed starting technique that completely turned the methods and basic cautions I usually recommend UPSIDE DOWN

This technique is called "Dense Planting" by Craig LeHoullier (well known among tomato growers)

I honestly don't think it should be recommended to new gardeners because I believe in learning the "basics" -- I.e. FOUNDATION TECHNIQUES -- first. In other words, and in ths case, how seeds/seedlings grow in ideal conditions and what they should look like when healthy. What causes the usual problems, what to expect, what are the signs of trouble, and how to prevent them.

I'm trying it out in a "modified form" now to see how it works and if I can be successfull doing this, because if it's possible, then it's a great technique for SAVING those weak spindly light starved seedlings that many beginning gardeners new to growing seeds post about.

So caveat emptor if you decide to try this yourself

https://nctomatoman.weebly.com/1/archives/03-2010/2.html

Note that he uses a fairy deep and large celled inserts in his standard 1020 flats. -- I'm trying it out with lettuce in similarly sized single container and cabbage, kohlrabi, eggplants and peppers in similarly sized 6-pack. I'm also trying this with lettuce, arugula, spinach, beets, and dill in clear plastic JUMBO egg carton to see if smaller, shallower containers typically used by beginning gardeners work.

Another note is that he grows a large number of plants for sale. A typical backyard gardener doesn't need to grow nearly as much.

He also waits until the spindly seedlings fill the cell with their roots -- he squeezes/pops them out. That might mean you'd want to use smaller cells for smaller number of seedlings, but that may affect how well they perform. Also, growing different kinds of plants in a multi-cell insert in a single tray isn't a good idea because they grow at different rates and need different growing conditions -- he grows same plants (different varieties) per tray.

*I'm already running into trouble because cabbage and kohlrabi seeds in the 6 pack sprouted in 2 days on top of the light fixture but eggplants and peppers are clearly not going to be up any time soon, and Lettuce and Arugula sprouted in 3 days in the egg case in the sunny windowsill, spinach are just starting to sprout and the beets and dill are still sleeping.)*

He also uses HEAT MATS for tomatoes and peppers for initial germination, and puts them UNDER LIGHTS for a while (This technique is not about starting seeds completely without using the usual seed growing tools like heat mats and grow lights) and then out in the sun every day -- Timing is critical and he watches the weather and doesn't Uppot until temperatures are warm enough. (He also seems to wait until awfully late to plant out the cold weather crops But maybe that's because his primary focus is tomatoes.... No denying his success there. )

[rainbowgardener]

I checked the link. Under the pretty flower pictures are some pictures of very crowded little seedlings, but no information about them, what he is doing or why...

The things I start on heat mats are often about that crowded, to conserve space on the mats, but I probably don't leave them that way as long.

[applestar]

Sorry, he goes into detail in the videos -- I've been looking at them several times already so forgot to specify what to look for.
I also thought if interested that you may look at previous and later pages since he chronicles the process from sowing seeds to growing them to sale size plants, mostly in videos.

In summary, what he does is starts them as many as 30-40 tomato seeds per 1.5" cell, covers with food wrap on heat mats in FRONT of upstairs sunny window. The trays are occupying a table and not anywhere close to the window itself.

They sprout spindly and tall, haphazardly as they usualy do, so he keeps the plastic wrap over them (he admits this is usually a "no, no"), and when all/most cells have sprouted, he moves them under the lights in the garage (cool temp). He keeps them there, dense and crowded in a state that I would not recommend, but I believe he does set them outside during the day which no doubt toughens them and pre-acclimates them for the next step.

When he finally uppots them, the roots have filled the cells. The weak stems flex easily and he is pretty casual about separating and ripping the roots apart. He pushes them down to bury all that spindliness in dry filled 4" pots which he says is looser/quicker and easier than pre-moistened mix. He times this to when he can put them all outside after a day of rest in the garage (NO GREENHOUSE) and only brings them inside in case of freeze (covering them outide in case of frost).

ANYWAY, my primary interest in this technique is to see if this is a viable, easily replicated way to rescue spindly seedlings. I have some overgrown tomato seedlings in micro cubes that I may subject to similar treatment and see how they respond in comparison to the others in mini cubes. I'm trying out the full overall technique with lettuce, etc. and see how it works. -- I will have to force myself to let them grow spindly.

... in fact now that I think about it, I put the little pot of lettuce in V8 Nursery too close to the light
(I'll take it off of the deli container pedestal )


Lettuce and Arugula sprouted in egg case on windowsill:


Cabbage and Kohlrabi sprouted in 6-cell in Winter Paradise (plastic wrap removed for visibility but will be replaced. I cut the corner of the wrap off for the fully sprouted cabbage though ):

[applestar]

Cabbage and kohlrabi:


Also posted about applying some of the techniques while uppotting tomato seedlings.

[Jardin du Fort]

If I recall, Eliot Coleman uses a mass seeding technique. He germinates the seeds in a 3" deep 1020 flat. After the seedlings show true leaves, they are "picked" out and transplanted into a 6" deep 1020 flat. There are no pots or blocks or anything else to separate the seeds or soil in the flats. Once the plants are ready to outgrow the 6" flat they should be ready for the garden....

Anyhow, that's my plan, if I ever get around to it.....

[imafan26]

I plant seeds in community pots all of the time. It saves space.
The smallest pots I use are 3 inch. I just don't have luck planting anything in cell packs.

It is important with this method to keep the plants growing; transplanting when the true leaves come out and the before the roots become entwined.

The root ball must be carefully teased apart to separate the plant roots when transplanting. Bottom watering and misting works best so the transplants don't get knocked down after transplanting.

I get 90-100% success this way with fewer dampening off problems. If there are any runts in the container, I can leave them to grow out more, but if I have enough plants already set out, I will either trash them or double them up.

[applestar]

Here's an update photo of the lettuce which have been uppotted and the remaining beets, spinach, arugula, and dill still in the egg carton:

All those seedlings in the pots came out of the two egg cells (smallest were put back in one of the cells). I have a small 2" pot full of lettuce that need to be uppotted too, but I'm taking care of the arugula in the egg cells next. Probably beets will get planted directly in the ground after that. The lettuce in the pot can be held off for the next succession.

Spinach didn't germinate very well and the few that did germinate seem pretty happy in the egg cells still.

[LA47]

Probably not something I'd try as I don't start that many seeds. I did see something sort of similar that I've used for years. It was called dense planting also. Mainly to be used for tiny, hard to sow seed, such as carrots and lettuce. Basically add a little sand and scattering the seed in the designated bed. No rows, Drives Mike insane as he is very organized person but it is the easiest for me.

[WinglessAngel]

I didn't know there was a method term for that lol. That's what I always do, but what I do is after they start coming up I use small snippers to cut all but the best maybe 4-6 seedlings before the true leaves come up and then after the leaves come up I again trim with small snippers to the healthiest 2-3 plants and up pot afterwards. I always try to grow a minimum of 2 plants together in the same spot in case one dies. It's never failed for me but everyone is different Part of it for me I think is just seeing all those baby seedlings come up and I love to watch them grow and tend to them but that's just me lol. I should mention though that I have some very large areas that I am able to garden in and fill up so the amount of plants I start always get planted but I do run into the problem of running out of pots to up pot to lol

[applestar]

This is a little bit different. The idea is that you can save all or most of them by separating and up potting them. This is what's caught my interest.

So far, it seems like as long as you give them good light within reasonable span of time, and expose them to the sun as early on as possible, the wimpy elongated seedlings can recover and become sturdy enough to be handled for uppotting.

They ARE somewhat less vigorous immediately after uppotting and need a little more care. I lost a bunch of cabbages and kohlrabis, but still have more. This method nets ridiculous number of seedlings.

[WinglessAngel]

That I can vouch for on the seedling counts. lol I did see that about separating the seedlings. I have tried that too in the past and it worked out alright, mostly though for sturdier plants, like my peas, those did fine. Smaller ones I shy away from separating but I do tend to snip them down to the healthiest still. I hope it works for you!

[imafan26]

I must admit I do use this mass technique. The trick is to keep the plants divided and growing. Not all of my seedlings will make it. The weakest ones won't get planted out. Sometimes I overestimate how many seeds I put in a pot, sometimes, when the pots don't germinate I overseed them and then the seeds sprout. It is actually not hard to separate very young seedlings. They do take careful handling, but with care over 90% do survive.

It is a way for me to save on space. Otherwise I have too many empty pots when the seedlings don't sprout or die.

[TZ -OH6]

Craig L. uses heat mats because he plants in his unheated garage. But there is not reason to do anything different than you usually do. I dense plant all the time. It is a safer and more stable seed environment than small 'pots' in that the soil doesn't dry out as quickly when you are not looking.


Even when planting multiple varieties I start all of one variety in the same container, which usually means five seeds per 1"x2" cell in a four pack insert. but that is really spead out compared to 40-50 seeds per 3" community pot, which I also use sometimes.


It works great for tomato and pepper, which take to repotting well.
I do it for potato seeds (TPS) but am going to stop because the seedlings are so fine and germination is spread out so there are problems separating the fragile seedlings later.