Holy smokes! My little seedlings just hung their heads in embarrassment, LOL. What varieties are they and when did you start them? They're huge!

kathyb -

As you can see in the picture, the seedlings were about 1" on March 10 - so 7 weeks old.from sprout. They are a mix of better boy, farm stand, super 100, and best boy.

I upgraded to T5 lights this year, and am using a new mix of supplements and nutrients. It seems to be paying off :)

Anyone have any tips for hardening off bigger plants? I assume the normal approach - but would appreciate any input.

I also have some large plnts to go out, though mine were an experiment in starting earlier. This wasn't the spring to try that I guess. Anyway, my plans for hardening off are the same as for smaller plants, but with a greater emphasis on stability of the pots in wind since all that foliage can really catch the wind and tip over those pots. Actually, I suspect the stems on mine are a bit brittle too, which is an added incentive to not have them tip over in the wind. Cheers!

Hardening off will be the standard route with greater wind protection as mentioned as they will be very prone to breaking.

But transplanting at that size is going to require extra work and care - much deeper holes or deep trenching and stripping off all the lower branches first - so I assume you know that transplants that size aren't really desirable?

Dave

digdirt - Thx.

Is the only downside the extra care - or are there other factors. I always plant my seedlings deep, etc, So do taller transplants lead to more problems overall - or just some more care? What is the ideal size, and why? Thanks again!

When hardening off big tomato plants lay the pots on their sides, so that the plants are horizontal (parallel to ground). The tops of the plants will eventually bend upward. This will make it easier to later plant most of the main stem sideways underneath the soil.
Also, by hardening them off sideways you minimize breakage from strong winds.

Last year I bought from a nursery, a beautiful - almost 3 ft. high - Brandywine seedling. Yes, it took extra-care to transplant, but it reached 15 ft. high, with some big yummy fruits.

I'm in southwest Ohio with 7-week old plants almost that big. I planted them three weeks earlier than usual (March 10) on purpose because I wanted to try wall-o-waters. I started hardening them off about 10 days ago. Each plant had a bamboo stake, the pots were secured to minimize the chance of tipping over and they were in a sheltered area with wind barriers. Unfortunately we've had a much colder spring than is usual, so I kept putting off planting them out and they kept growing. I planted them in containers yesterday, burying 6-8 inches of stem. Getting them inside of the WOWs was a delicate operation. Several of them are as tall as the WOWs. I'll probably have to remove the WOWs in 10 days at most, so I'm not sure this was a great plan. The jury is out.

I have T5 lights too, and my tomatoes grow very fast. I'd have to plant out at 4 weeks to have seedlings under a foot tall. So I'm used to big plants. They do seem to produce fruit a couple weeks earlier than the tiny plants my neighbor gets from the big box store and plants at the same time.

digdirt - Thx.
Is the only downside the extra care - or are there other factors. I always plant my seedlings deep, etc, So do taller transplants lead to more problems overall - or just some more care? What is the ideal size, and why? Thanks again!

The ideal size for a transplant is 6-8", maybe 10" tops depending on the inter-node length.

Much beyond that they are much more prone to breaking, more difficult to support adequately, more prone to wind damage, and most importantly, more transplant shock. Thus they tend to take longer to recover from transplanting than smaller transplants do. Their root development has often been retarded so is insufficient to support all the top growth. That means it takes the root development needed that is triggered by transplanting longer to catch up. The result is a stressed plant that has to be monitored carefully.

Plus if they are so large that they have already kicked into boom mode those blooms have to be removed to put them back into growth mode.

Trench planting horizontally so that only the very top set of leaves is left above ground will lessen the problems. It brings the top growth and root development back into a sort of balance and lots of new roots will develop all along that buried stem as well.

Many folks seem to feel that the bigger the plant when they buy and/or plant it the sooner they will get tomatoes. But research shows that just the opposite is true. Smaller, less stressed transplants will always catch up quickly and surpass the bigger stressed plants in long term health and production.

Dave

I have a question. my transplants are in 4" pots and I am assuming that they will stay in that size pot? Also, in terms of hardening them off, I'm in zone 5B - Montreal. We have started to get some decent temps. Is it too early to start hardening off? Some of my seedlings are about 2", some smaller. Normally we don't plant out until the around the 20th of May or even a week later to be safe.
Thanks, Sharon

There is no need to harden off until 7-10 days before planting out as once hardened off they need to be able to stay out. And yes, in your zone it is a couple of weeks too early IMO.

Everyone seems to want to rush the season. Not sure why when the price one pays can be very high.

Dave

Sharonie wrote: > my transplants are in 4" pots and I am assuming that they will stay in that size pot?

Being in zone 5b, I suggest you to repot. It will be a while until transplanting, and by then, the roots will be too crowded in the 4’’ pot. I suggest you to use these CowPots - 6".

>Is it too early to start hardening off?

I think it’s too early.

>Some of my seedlings are about 2", some smaller.

They are way too small to harden off, imo. I think they should be at least 5-6'' high.

Thanks Dave and Daniel. It's so tempting to want to put them outside but my instinct told me too early, so thank you for the information. Do you agree Dave that I might repot into 6" pots or leave them in 4"?

Can't really say without seeing them but if they are only 2" tall and smaller then 4" pots should be fine IMO. I have hundreds of 6-8" transplants currently in 4" pots waiting to be planted next week here.

I would have to disagree with using the cow pots, or any of the fiber-type pots, however. Far too many issues with them to suit me. if you do use them please be sure to strip off all the pot prior to transplanting them.

Dave

digdirt wrote: There is no need to harden off until 7-10 days before planting out as once hardened off they need to be able to stay out.

Can you elaborate on that? Will a hardened off seedling not continue to do well if brought back inside? I've been taking my seedlings outside on warm days, thinking I was helping them along. Is that a mistake? I'm still 2-3 weeks out from planting.

Sharonie wrote: > Do you agree Dave that I might repot into 6" pots or leave them in 4"?

Dave replied: > Can't really say without seeing them but if they are only 2" tall and smaller then 4" pots should be fine IMO.

The reason why I suggested repotting is because Sharonie - being in Montreal, Canada (5b) - will probably transplant her seedlings in about 1 month from now. In one month, imho, a 2’’ seedling will grow pretty tall, with crowded roots in that small 4'' pot. I don’t know what kind of pots Sharonie is using: if she uses plastic pots, the roots will be contorsionated in the 4’’ pot. If she uses cowpots, the roots will penetrate the pot’s wall, and that is not a big problem.

Dave wrote: > I would have to disagree with using the cow pots, or any of the fiber-type pots, however. Far too many issues with them to suit me.

Can you share with us those issues? I used cowpots for the last 2 years and everything was fine, no issues whatsoever.

I really believe what I see in this

where they compare two plants in two different types of pots: plastic and cowpots. I like the plant in the cowpot.

Dave wrote: > if you do use them please be sure to strip off all the pot prior to transplanting them.

While some say, it's ok NOT to strip off the pot, I always did and I mixed the pot with the soil where I planted my tomatoes. It’s cow poop, a fertilizer after all.

This post was edited by Daniel_NY on Mon, Apr 29, 13 at 1:32

I planted my Park Improved Whopper and Beefsteak Tomatoes under T5 lights also and they are now about 8 - 10 inches tall. The nights here are now about 48-52 degrees. I started the hardening-off process yesterday by placing them outside in a part sunny/part shade area for 4 hours. I will continue this process, increasing the time and amount of sun for 7 days. The final day I will leave them out over night if the temp is above 50. Then I will transplant them. As an experiment, I transplanted some tomatoes into the garden without hardening and I have been covering them at night for 8 days. Most seem to be doing well. Out of 9 plants, two appear to be suffering.

digdirt wrote: There is no need to harden off until 7-10 days before planting out as once hardened off they need to be able to stay out.
Can you elaborate on that? Will a hardened off seedling not continue to do well if brought back inside? I've been taking my seedlings outside on warm days, thinking I was helping them along. Is that a mistake? I'm still 2-3 weeks out from planting.

Sure. Taking young plants out for an hour or so to get some sun and fresh air is one thing. Is it necessary? No. Is it beneficial? Maybe, if done very carefully. Can it be risky? Yes. But that is not hardening off.

The process of hardening off is done to permanently adapt the plants to the totally new and different environment they will now be living in. Take them in and out and in and out over long periods of time and they never adapt because the environment is constantly changing.

Think of it as moving. You bought a new house, go through the process of gradually moving all your stuff to it a little at a time, and 1/2 way live in both houses for a week or so with all those frustrations. Finally you settle in to the new house. Are you then going to go back to the old house to live when everything is over at the new house? Nope, once you are moved, you are moved, right?

So when it is getting close to planting time they need to adapt to that environment. Gradually they go out into it, learn to live in their new house. Now if you take them back to the old house for any length of time after they have adapted to the new one, they have to re-adapt all over again and again.

Make sense?

_________________

Daniel - if she needs to repot later on that is fine but she sure doesn't need to do it now. And a 2" seedling would be over-whelmed in a 6" pot.

And how much growth the plant has in 1 month all depends on the growing conditions provided. If they are given the proper cool growing conditions with plenty of light then a 4" pot will be fine for a month and the plants will be approx. 7-8". Will it be rootbound? Possibly but plants can survive just fine for a brief period until they can be planted.

If they are exceptionally warm conditions with not enough light then yeah they will be taller and lanky. But even transplanting to a larger pot won't prevent that from happening.

If you are happy with cow fiber pots that's fine but I have tried them and been sorely disappointed. The issues associated with using them are well documented and have been discussed here may, many times. The search will pull up all sorts of discussions about them as well as Jiffy pots, many with pics of the problems.

They do not compost in the soil unless you have lots of clay that will retain water for a long time around them. Folks have posted pics of them in the soil a year later.

Roots do not penetrate them as advertised unless the pots are kept overly wet. Folks have posted pictures of pulling up plants with the pot still intact and filled with roots but none outside the pot.

To keep the pots wet enough that means the plants have to be kept overly wet since the pots pull the water right out of the soil. That leads to root rot and stunted plants, yellowing leaves, fungus gnats, etc.

It's your choice but IMO plastic pots will always outperform any of the fiber pots. If one wants truly direct planted pots of some kind use newspaper pots.

Dave

This post was edited by digdirt on Mon, Apr 29, 13 at 18:39

Dave, thanks for the information. I'm relieved about the hardening off, because I felt it was too soon. Don't think I'll repot. And some of my seedlings are in Jiffy pots which I dislike immensely. I agree with what you said about them. I always remove them completely when I plant because I don't like the idea of my plant contained in anything. I also feel the plants are more at risk of breaking because the jiffy pots become so fragile over time. I prefer the plastic pots.
My plants are getting lots of light and they are in a cool space. They are starting to take off in the last few days.

So when it is getting close to planting time they need to adapt to that environment. Gradually they go out into it, learn to live in their new house. Now if you take them back to the old house for any length of time after they have adapted to the new one, they have to re-adapt all over again and again.

Make sense?

It does. I've often wondered if plants spending time outdoors get (for lack of a better word) "tanned", such that they don't photosynthesize as well when they come back inside. If that's true, then it would make sense that it would take some time for plants to get used to the indoors again.

My tomatoes (indeterminate) grew to a foot tall, and started flowering. I removed the flowers and top leaves and have up potted them to 6 inch pots. Today, I "pruned" off the bottom couple leaves, when I put them in deeper in the 6 in pots. We have another 3-4 wks before I dare plant them out in my raised beds (Ann Arbor, MI area). They are now regrowing new tops after only 10 days. No longer under lights, but sitting around in windows. I exercise them with an oscillating fan. Will the top pruning and removal of suckers cause any problem down when put in the ground. Alternatively I could start again, since I have heat mats and lights and they'd be 5-6 inches in a month.

"Will the top pruning and removal of suckers cause any problem down when put in the ground."

If I understand your post correctly it isn't the ideal approach but they will most likely recover if planted deeply in the garden. The problem with topping indeterminates is that it just stimulates more new top growth but with a somewhat compromised circulatory system in the new growth. And by removing the low growing so-called "suckers" you will have sacrificed the fruit they would have produced and stimulated the growth of additional ones higher up the stem but the low ones removed won't be replaced. How much of a difference that makes to you all depends on how much aggressive pruning you plan to do once in the garden.

If they can't go to the garden for another month I assume the problem is that you started them far too early? Something to keep in mind for next year. :-)

Dave

Thanks, exactly, I started them too early, seeded on March 10th in cell packs, 2nd leaf (real) 3/19, up potted 3/23, 4/6 and finally 4/21 to 6 in pots. First year using heat mats, and light rack w/2 ea 2x4 fluorescent bulbs. Did not realize what a difference the combination of bottom heat and lights would produce.

I actually espalier my tomatoes on cattle panel which is extended to about 8 ft with additional bamboo supports in raised beds. The raised beds (12-14 inch) are about 70% compost green (garden debris & horse manure & brown leaves & marsh hay from the previous season). Last year I purchased tomatoes and removed all leaves as they grew to about 2-3ft off the ground, under planted w/beans and mulched w/a layer of newspaper cover w/marsh hay.

I usually plant my tomatoes leaving only 2-3 leaves above ground, and remove them as the plants grow and allow leaves to remain at 2-3 ft off the ground.

Actually although I remove the low leaves they did re-sprout continually during the season usually just above the axis of where the leaf had been removed.

I've read conflicting accounts of removing the "suckers" the leaf growth that emerges between the primary leaf and the stem. Since I've never allowed them to grow, questions is would they produce fruit. They seem to grow much like "suckers" on woody plants, so that the top growth is overtaken by the faster growing suckers.

Since we have a wk long forecast of above 40 degree nights and 60 degree days w/overcast, cloudy, and rain for the week I'm going to "practice" with some of my plants hardening them off. I have 2-3 times more tomatoes than I intend to put in the garden. Again didn't expect the fruitful germination and continued survival.

I am going to start some more seed tomorrow, since I had 5-6 inch plants in 5 wks. Will be an interesting test to compare the growth over time of smaller seedlings with my current pruned. As well as test their survival and acclamation to the temperatures now. Photo showing in 4 in pots on 4-18 would have been nice size to plant out and seedlings on 3/19 Too Anxious to try new system.

Dave, this is last year, Sept 2, Tomato on fence w/underplanting of Beans. Tomatoes in photo are Burpee Super Sweet 100 Hybrid