hardland
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Fertilizing seedlings? How often and with what?

I started about 10 toms 2-3 weeks ago in small jiffy pots. The sprouted in about 5 days, pretty normal. They just seem very slow to grow. I water every morning and have been using a little fish emulsion every 6 days. They are outside in good light during a quite nice Florida fall period(80' low humidity) I wonder if I need to fertilize more often. Any thoughts?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

Stepheninky
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What type of soil/ starting mix are they in? And how old exactly are they? How many true leaves do they have?

Usually most standard seed starting / potting soils have plenty of nutrients and no fertilizer is needed or recommended.

To go into that further IMHO you do not want to use fert in till the plants are in there final location. If the plants are young they have what they need to grow and establish their root system.

Normally most will only grow about an inch a week. It also depends on the type of tomato as well, if it is dwarf or determinate the plants will be shorter and more compact in the seedling stage than an indeterminate would be.

Let us know some more details and we will be able to help much better.

hardland
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Stepheninky wrote:What type of soil/ starting mix are they in? And how old exactly are they? How many true leaves do they have?

Usually most standard seed starting / potting soils have plenty of nutrients and no fertilizer is needed or recommended.

To go into that further IMHO you do not want to use fert in till the plants are in there final location. If the plants are young they have what they need to grow and establish their root system.

Normally most will only grow about an inch a week. It also depends on the type of tomato as well, if it is dwarf or determinate the plants will be shorter and more compact in the seedling stage than an indeterminate would be.

Let us know some more details and we will be able to help much better.
I mixed 50% seed starting mix and 50% organic potting mix. I do this because the seed mix alone seems to dry very quickly. Potting mix seems too heavy on it's own. The seedlings are 3 weeks old, they sprouted after 5-6 days. I am growing purple russian, cherry, sweetie and heatwave. The cherry is a lot smaller than the rest. I have read other growers water with a pinch of fish emulsion every 3 days. I'm using jiffy 3 inch pots, then I usually re pot into jiffy 6 inch pots, then in the ground for real. Thanks
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

Stepheninky
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Joined: Tue Oct 05, 2010 11:02 pm

I am doing a indoor grow over the winter to try and get some seeds of a couple of wild tomato crosses for grow out in our regular season here in spring. seeds were planted 2 weeks ago, they are about 1 1/2in - 2in tall and starting to develop true leaves. (mine the humidity and temp are monitored pretty closely so my results might vary from yours) As I posted if you are averaging about an inch per week you are doing fine. They are still young and need to develop their root systems to support the new growth. Once they get the roots going the will jump.

I do not use any fert though I just pot up using regular old Miracle Grow potting soil which has a slow release fert already. Have never had any issues with it. I do use hydrogen peroxide with water to water my seedlings. It prevents dampening off, does not harm the plants and breaks down into hydrogen, oxygen, and water which the plant can use.

Here is a pic of mine hopefully they will make you feel better about yours lol

[img]https://i622.photobucket.com/albums/tt301/Superfrk34/closet%20grow/IMG00094.jpg[/img]

TZ -OH6
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It depends on the potting mix. I get much better growth from Promix BX, and I may not fertilize until just before transplant, but with many other mixes the seedlings will often stall out a little while after potting them up and need at least one shot of 1/4-1/2 strength MG-type fertilizer. If it seems like the plants are stalled (and it is not a watering problem) they probably are.

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farmerlon
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I never add fertilizer to transplants while they are in the pots or flats; I just let them grow with the standard potting soil.

I'm not saying that's the best way, and not saying that is what you should do... but, that works for me. :)

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rainbowgardener
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If there was any fertilizer in the potting soil (usually is) and you have been adding fish emulsion every week, they have plenty of nutrients.

If they are really not growing, I'd think about other causes. You said you are watering every AM and they are in peat pots. The peat tends to hold water, they could easily be overwatered, getting waterlogged. That slows growth down because oxygen can't get to the roots.

Otherwise, what kind of light do you have on them? Usually not enough light causes them to grow tall and spindly, but if they were seriously deficient in light, it might slow growth down.

But since you haven't said how tall they are or how many pairs of leaves, I can't tell if maybe you are just impatient. Three weeks isn't a real long time. Picture would help.
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hardland
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rainbowgardener wrote:If there was any fertilizer in the potting soil (usually is) and you have been adding fish emulsion every week, they have plenty of nutrients.

If they are really not growing, I'd think about other causes. You said you are watering every AM and they are in peat pots. The peat tends to hold water, they could easily be overwatered, getting waterlogged. That slows growth down because oxygen can't get to the roots.

Otherwise, what kind of light do you have on them? Usually not enough light causes them to grow tall and spindly, but if they were seriously deficient in light, it might slow growth down.

But since you haven't said how tall they are or how many pairs of leaves, I can't tell if maybe you are just impatient. Three weeks isn't a real long time. Picture would help.
I'll put a pic up tommorow. I may be over watering, they are in good sun light, outside on a screened in patio. It's been beautiful here in FL recently, 75-80 degrees and very low humidity for us. Is it wise to bring your seedlings in at night?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

TZ -OH6
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Around here there are two reasons to bring seedlings inside at night...Frost and deer. They stay out all night once both are no longer a threat.

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rainbowgardener
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agree with TZ (as usual!) No reason to baby them any more than needed. If they are growing outdoors in the conditions they will be planted in, they will be adapted to that. If they spend significant time indoors, then you will have to harden them off, that is gradually transition them to the outdoor conditions.
Twitter account I manage for local Sierra Club: https://twitter.com/CherokeeGroupSC Facebook page I manage for them: https://www.facebook.com/groups/65310596576/ Come and find me and lots of great information, inspiration

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applestar
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Couple more ideas:

On the flip side, if you are "watering" only very lightly, the peat pots could get dried out and end up killing off the developing roots.

When seedlings are in too small pots, their growth can also stall.

We'll probably be able to tell from the pictures. :wink:

hardland
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Here is a picture of the seedlings. I think they look quite healthy, as I noted earlier, they sprouted after 5-6 days but have only grown to about 4 inches. I started the seeds Sep 16th, so its just over 3 weeks. I have 9 on the go and stepped 3 up to larger jiffy pots, 6 inch yesterday. Thanks for any input.

[img]https://imagehost.vendio.com/bin/imageserver.x/00000000/valuemet/seedlings.jpg[/img]
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

TZ -OH6
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Based on the plant to pot ratio there should be plenty of nutrients in those pots (even in unfortified mixes) to get the plants larger than they are.

I once had students grow several hundred tomato and pepper seedlings in cell trays sitting in shallow pans of water (a trick I learned from a research botanist), so constant moisture won't automatically be a problem (it is more of a problem with bigger pots watered from the top). Letting the peat pots dry out could be problematic, which is why peat pots and peat pellets are not used by many people.

hardland
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So it seems my tomatoe seedling are stunted. Could it be the seeds, they are probably 18 months old?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

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rainbowgardener
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Nope, not the seeds. They either sprout or they don't. If they sprout then the seed has no further effect. I have used five year old tomato seed. The germination rate is reduced at that point, fewer of the seeds actually sprout, but the plants that result are just fine.

But they do look stunted and not thriving for how old they are.
Twitter account I manage for local Sierra Club: https://twitter.com/CherokeeGroupSC Facebook page I manage for them: https://www.facebook.com/groups/65310596576/ Come and find me and lots of great information, inspiration

hardland
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Any suggestions as to what the problem might be? Could the fact that they are behind a screened patio be the problem?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

TZ -OH6
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From the information given I don't see anything wrong, but there might be some critical detail missing.

Its hard to tell what the light level of a screened in porch might be. Filtered direct sun (similar to dappled shade) would be better than direct sun, but if the plants are in a screened porch back away from the screens and the porch is shaded by trees you could be in trouble (but I doubt it, assuming you have a bunch of flowering houseplants growing there too.). The shoplights many of us use to start seedlings are not very bright compared to shaded sunlight, but they are much brighter than normal room/reading light, and they are on for an extended period, which is why they are better than window light, which is only bright for a few hours until the sun passes away (we tend to have little windows up north).

Low light would cause elongated plants. Yours just look like runts, which is generelly a water stress/nutrient problem.

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