Potting up

[amideutch]

I pot up to 4" Cowpots or 4" Dot Pots using Fox Farms "Light Warrior". Ami

[TomNJ]

Hi Dennis,

I've been raising my own tomato seedlings for over 30 years and never potted up. As I mentioned, I do lift out and move about 30% of the seedlings to have a strong plant in the center of each pot, and this is equivalent to potting up, but in all these years I have never noticed that these plants were different than the others. All my plants are essentially equal, both in the pots and in the ground.
The only scientific study I have ever seen on the benefits of potting up was from 1927, and if I recall correctly the potted up plants did not produce a higher yield.

I've read that if the tap root hits the bottom of the pot that this also forces a fibrous root structure - perhaps someone with more knowledge can comment. Since my pots are 3.5" deep, the tap root hits bottom real fast, within a week or two. My plants are garden ready in 5 weeks, and the dirt balls are full of roots.

I do use heating pads and keep the soil temperature in the 80s F until all the seedlings are up, then remove them. The lights and fan are on timers, the lights for 16 hours and the fan for 3 hours/day.

TomNJ

[TZ-OH6]

I pot up into the same basic potting mix that the seeds were put in (ProMix, etc). Most of the time I find that I do have to fertilize or the seedlings stay at a few inches high, even if the mix says that it has starter nutrients.
I start all of my seeds of a given variety (usually about 5 seeds) in a small cell and then pot them up to 3" to 5" pots when they get crowded (1 repot). This saves on space under the lights. At the time of repotting it is often warm enough here during the day that I can take advantage of sunlight.


The root studies TomNH mentioned are here (see links). There are actually two or three studies discussed, and it can get confusing. One focusses on the effect of multiple repotting (more than one is not beneficial to the plants, but is used to conserve greenhouse space). one stdy or part of a study looks at the use of large individual pots (4-6") for seedlings (beneficial) vs seedling flats or small pots (not as good). The other study focusses on root development between direct sown plants (seeds planted in the garden) vs seeds started in pots and then transplanted. The transplanted ones developed fibrous roots, because of the root disturbance caused by transplanting, and grew faster because the direct sewn ones tended to send a tap root down into the colder deeper soil. The two studies are not adequately separated in the discussion, so there have been forum discussions arguing about how many times to pot up for the best root development.

http://www.soilandhealth.org/01aglib...010137toc.html

more specificlly this tomato chapter

http://www.soilandhealth.org/01aglib...10137ch26.html

[mtbigfish]

TZ
Thanks for the info makes me feel like the last 51 years I have done something right!!!

[TomNJ]

My read of the 1927 study is that starting tomato plants in pots and then transplanting into the field is better than direct planting into the field. With respect to potting up, they conclude that starting the seeds in larger pots with no further potting up gives better tomato yields than starting the seeds in smaller pots and potting up. Here is a quote from the study:

"Since the root system is disturbed and the development of the plant more or less checked at each transplanting, it might be concluded that plants grown from seed sown directly in pots or other containers would grow more vigorously and give a higher yield than those once or twice transplanted. In fact this has been shown by numerous investigations to be the case. That transplanting in itself does not promote an early crop nor an increased yield has been also clearly demonstrated.

In an experiment in Wisconsin, three crops of tomatoes were grown . . . In each case seeds were planted singly in 6-inch pots in the greenhouse; when the plants were about 2 inches in height, two-thirds of the whole number were dug up and reset in the same pots; later, one-half of these were again transplanted in a similar manner. As soon as weather permitted, 10 plants of each lot were knocked from the pots and set 4 by 8 feet apart in open ground, every precaution being taken to avoid injury to the roots.

Those not transplanted yielded more than those once transplanted, while those twice transplanted yielded least."

Personally I see no benefit to potting up and I never bother. I just start them in 3.5" pots and leave them there until transplanting into the garden.

TomNJ

[mtbigfish]

we stand informed - at least from 1927 and Wisconsin study

[PNW_D]

Potting up highly recommended in 1890 for earliest fruit .... I've included a bit more just for interests sake ... seems Google Books is picking up more and more of these old texts


This section is from the book "The American Garden Vol. XI", by L. H. Bailey. Also available from Amazon: American Horticultural Society A to Z Encyclopedia of Garden Plants.
Tomatoes At Cornell Experiment Station

Bulletin X, of Cornell University Agriculture Experiment Station gives the results of Professor Bailey's experiments with tomatoes. In most of bis conclusions we heartily coincide. The writer has long insisted that frequent transplantings are absolutely necessary to the production of early fruit. We have frequently had people tell us that they had rather have tomato plants raised in the open ground than hot-bed plants. So had we, if by hot-bed plants are meant the slim, crowded, almost rootless plants produced by sowing seed in a late hot-bed and growing them without transplanting until set in the open ground. Such plants are practically worthless. I fully agree, then, with Professor Bailey when he says that "frequent transplanting of the young plant, and good tillage, are necessary to best results in tomato culture".

Years ago I insisted, and have seen no reason to change my opinion, that no amount of forcing could overcome the matter of age necessary for the plant to attain before fruiting. I have never yet seen a tomato that will produce ripe fruit in less than four months from the seed, and most of the larger sorts require a longer time. Some years ago one of the stations, in an experiment with tomatoes, claimed to have proved that the forwarding of the plants under glass was of no advantage in the early production of ripe fruit, though every market gardener of experience knows that exactly the opposite is the fact, and the grower who would expect to compete with his neighbors in the production of early tomatoes without the use of glass would be looked upon as an ignoramus. In the experiment referred to it appeared that the ' forwarding" under glass referred to was sowing the seed about middle of April in a hop bed and transplanting these at same time with plants raised outside. That such " forwarding " is useless any practical gardener will admit, for these tender, small-rooted plants underwent a check which gave the robust out-door plants a decided start and they should have been called "retarded" plants.

Professor Bailey's experiment showed that "plants started under glass about ten weeks before transplanting into field gave fruits from a week to ten days earlier than those started two or three weeks later, while there was a much greater difference when the plants were started six weeks later. Productiveness was much increased by the early planting".
This is "forwarding" under glass, properly speaking. Plants from seed some ten weeks before setting in the open ground must perforce be transplanlanted two or three times under glass, and at each transplanting and gradual change to a coolor atmosphere make a gain in vigor and hardiness. This is a point which Professor Bailey does not mention, but which is of importance in the production of the best and earliest plants - that while the plants should be started in a high temperature they should at each transplanting be placed in a cooler temperature, with plenty of ventilation to secure a stout and stocky growth.

My practice is to sow the seed in boxes in a hot-house (650 night temperature), about two and a half months before time to set in open ground. (This would make it here the last week in January.) As soon as the plants are up large enough to handle, they are transplanted into other boxes about two inches apart and placed near the glass in a house where a night temperature of not more than 500 is maintained. As soon as they make two pairs of leaves above the cotyledons the growing tip is pinched out, and about four weeks before putting in the open ground they are transplanted into cold frames, putting about 65 plants to a sash, 3x6 feet size. Every effort is then made to give them exposure to the outer air on warm days and finally full exposure a few days before final transplanting. They will then be found to be stout plants, with two or three branches, and a main stem as thick as one's finger, but not more than eight or ten inches high. They will easily lift with a mass of roots and soil larger than a man's fist, and will go right on growing and making fruit.
The pinching has caused an early development of the side shoots which always produce the first fruit.

Professor Bailey well says that a "tall weak plant with a cluster of bloom at top" is not worth planting. Such clusters of bloom do not give the earliest fruit, ii they give any, and the plant stands still until the side shoots appear. Another point in which my experience corroborates Professor Bailey's conclusions, is that liberal manuring not only does not retard to any appreciable extent the earliness of the crop but largely increases the smoothness and quantity. The exception to this is the case of a heavy clay soil. In such a soil, naturally fertile, a heavy coat of manure made too rank a growth of vines and a greater tendency to rot; even then there was an improvement in smoothness and solidity.

Professor Bailey says varieties "run out." No doubt this is usually the case, because of the tendency of tomatoes to "sport" continually, thus requiring great care in the saving of seed to keep a type pure. But that they necessarily run out, I am not ready to concede. Our improved tomatoes are composite varieties, and therefore have a tendency to break toward some one or other of their ancestral stock. But did Professor Bailey ever know an original variety of the tomato to run out ? The Cherry, Plum and Pear tomatoes are as pure to-day as ever, and the old, big, rough, Mexican tomato will always reproduce itself, the "Garfield" for example. But put the Mexican tomato into the smooth skin of the Cherry, and it at once tries to get out.

Professor Bailey names as best for market, Ignotum, Beauty, Mikado, Perfection, Favorite and Potato-Leaf, I do not object to any of these except Mikado; with us it is entirely too rough and uncouth for a market tomato, but is good for table and very productive. Neither can I agree with him in condemning Dwarf Champion for market. With me, and I grew several thousand of it last year, the Dwarf Champion is the earliest, smoothest tomato of good and even large size I have ever grown. While not of the best quality for family use, its tough skin and the fact that it gives nearly the whole of its crop early make it valuable for distant shipments. With us it is by no means small, being from good medium to large. It is evidently a recent cross between Acme and the French Tree tomato, as last year many plants in our patch reverted to these two types, and some others had the fruit of the French Tree with the vine of the Acme, and its rotting quality, too, while the pure Dwarf Champion, was as free from rot as any I ever grew.

For strictly early market sort I think the Dwarf Ccampion is as yet at the head of the list.

Bulletin X is one of those practical papers for which the Cornell station is becoming noted, and for distribution to the class of cultivators for which it is intended is worth a great deal more than scientific formulae and tables which they cannot comprehend.

N. C. College of Agriculture. W. F. Massey.

[pacmanJohn]

I greatly appreciate everyone's input. Thank you all. Barbee, I use two 4' shop fluorescents, each with one normal 'warm' bulb (probably 7 years old) and one 'cool' bulb (a couple years old). I use Miracle Grow Seed Starter mix. I think I started too early last year as well, having to leave them under the lights for close to 8 weeks before I started hardening them. That probably didn't help.

Sounds like I may try different bulbs (do you agree?), heat pad and some fan action and start working them outside quicker. I did build a make-shift green house that is 8' x 8', but has no electricity. I will also have to work on some air circulation in there. I'll do some research on the using water to help insulate (I am guessing that is how it works).

Thank you all again. And I'll still take any advice that you guys have.

[Barbee]

John, I have the 4 bulb 4 ft lights and I have heard people say they can run the same bulbs for 2 or 3 growing seasons, but I have never had much luck with re-using bulbs and replace mine every year. I use 2 of the pink grow lights and 2 regular lights in my fixtures. The grow lights are pricey though and I'd love to be able to figure out a way to get 2 seasons out of them. I thought about wiping them down this year but in all honesty, will probably just go on and replace them.

I don't use a heat pad or a fan, but I do "pet" the mater babies every day which I feel makes them stockier and also gives me my tomato smell fix I know plenty of people who use fans and they grow nice seedlings, so I don't think you can go wrong with the fan. I really can't comment on the heat pad, since I've never used one. Maybe someone who does use one could comment on what temp they set it at, and for how long they use it, etc.

As far as having a bad luck last year, that could very well be due to the weather. It was cold and rainy and just awful for trying to get maters going after planting out. I had gorgeous transplants at set out and then that cold wet spell set in and I thought I was going to lose all of them. They recovered finally but it really affected production.

[amideutch]

One of the many reasons I use biodegradable pots (CowPots/Dot Pots) is because of
transplant shock. After potting up my seedlings grown in Jiffy 7's into CP's or DP's that is where they stay till I pull the plant in the fall. The plant and pot are put into the container or ground after being dipped in a solution containing Actinovate and Mycorrhiza, couldn't be simpler. And when I do pull the plant at the end of the growing season the pots for the most part have totally decomposed or there may be a small portion left at the top. Ami

[Barbee]

Ami,
Was it you that posted the photo of the cow pot with the roots growing thru it? I got some cow pots free last year at a seminar and liked working with them but I got them too late to see how well they held up to wear and tear of daily watering.

[yotetrapper]

Is there anything that makes the cow or dot pots better than Jiffy pots? I'm guessing there must be considering they're double the price?

[TomNJ]

PNW - Interesting excerpt, but it seems what they are saying is that transplanting is beneficial to give crowded plants more room and and a cooler soil to grow in. I agree that leaving plants crowded and hot will cause them to become root bound and retard growth, but if one starts the seeds in a larger pot to begin with, then this is not an issue. It doesn't really address any benefit from disturbing the roots, which seems to be the basis for justifying potting up.

Barbee - The heating pads help speed up germination but are not needed after the seedlings are up. In fact, after germination the plants prefer a cooler soil. I set my heating pads to give a soil temperature between 80F and 90F at 1/4 inch deep. After the plants are up I remove the heating pads and allow the soil to cool to my basement temperature, about 65F.

The fan provides air circulation to prevent damping off while the seedlings are small, and also helps move the plants to promote stronger stems. I leave the fan on for three hours per day on a timer.

I start hardening off about three weeks after germination depending on the weather. Initially I place them in the shade for an hour or two if the air temperature is above 60F, then gradually expose them to sun, starting with morning & evening sun and graduating slowly to full afternoon sun. They come back inside at night until a few days before planting in the garden. In those final days they are outside all day so there is little or no temperature shock at transplanting time.

TomNJ

[amideutch]

Barbee, the pictures were mine. Yote, the difference in the pots is what they are made of and how well they break down. The CowPots are the most expensive and are made from cow dung. So as they decompose they feed the plant. The only way to buy 4" CowPots is the 300 quantity count which is around $125.00. Smaller quantities are to expensive.
DotPots sold by Johnny's are made from wood fiber and the 4" x 4" pots are 50 each for $14.95. I used these and CowPots last year with good results.
The Jiffy Pots are made out of Peat Moss and wood pulp and the unit cost is 14 cents apiece. I've read that root penetration in peat/wood pulp is not that good and the pots do not readily decompose. I have no experience with Jiffy peat pots but I do use the Jiffy 7 peat pellets which I highly recommend for seed starting.
While I was researching the costs of the other pots I found there is another product on the market called FiberGrow pots that are made out of recycled paper and the 5" pots run $100.00 for 250.
So CowPots are the most expensive 40 cents apiece followed by FiberGrow pots at 25 cents apiece and Dot Pots at 30 cents apiece and Jiffy's at 15 cents a copy. So maybe the old adage that you get what you pay for is applicable here.
One word of note. Tomatoaddict has used CowPots also and said that Peppers she transplanted to CowPots did not do well but here tomatoes did fine. As I don't grow peppers I can't say. If you want to try peppers maybe try one or two plants to see if you get the same results as Terry.
These type of pots have lent themselves beautifully to the way I want to grow my tomato seedlings. Is this the best way for you to do it, maybe not. But other than sowing seed directly into the ground these pots provide the least amount of transplant shock to to your seedlings. With climate change going on and disease issues we had last year we need all the help we can get and a healthy plant is one way to assure a successful harvest. Ami

[chalstonsc]

Does anyone know of any studies comparing results from seeds started during different phases of the moon?