move seedlings from germinating mix to something else?

I'm starting seeds indoors for the first time. Apparently some folks transplant seedlings from germinating mix to a different type of soil in a larger pot before moving them outdoors. I don't want to crowd my babies, but if I move them to bigger pots they won't all fit under my fluorescent light. And if I move them to bigger pots, what type of soil medium should I use?
I'm using Gardener's Supply germinating mix. I also bought their "Plant Health Care" which contains fertilizer and various organic nutrients. I'm wondering if, after they sprout, would it be enough to feed them PHC? I think the germinating mix is soilless, so I don't know how long the seedlings can safely stay there.
I've read all about lights, keeping them moist by wrapping in plastic, how to water from the bottom, the need for ventilation to prevent damping off. This is the only thing that still baffles me.

The only seedlings I have transplanted in bigger pots are things like squash and pumpkins. I only did this because I orginally started them in pots that were too small and they quickly outgrew them. Other than that, I have never transplanted, I just waited until it was time to put them in the ground. I use almost soiless mixes and in the past I never even fertilized until I planted them and they always did fine. I did use fertilizer this year though and it has made a difference.
Need a little more specific info about your seedlings. What kind of seeds, how do you have them started (like in individual cells or just sown in one large pot, etc.), how close are they together? We'll be able to give you a better anwer to transplanting.

jasper.... I start everythign in a soilless mix. You cna keep them growing in the soiless mix as long as you feed them a week solution of say like miracle grow.

Once those seeds sprout, they only have between an average of 7 to ten days of food in their seed coat. After that they will start going don hill as they will starve.

At about 6 days I start with the weak miracle grow and water them with it for all the waterings then maybe about every fivfth watering, I just giv ethem regular water to flush the salts out of the little tray and then it back to the weak miracle grow.

Once they have their second set of leaves then I go to the regular strength of miracle grow and again use it all the time and a clear rinse of plain water feed every so many days.

I am a grower, an what I use is the Jungle Soil Professional growers mix with fertilizer from Lowe's. It is the onyl place that carries it. You get 3 cub feet and it a big bag and it only abotu 12 bucks , same as miracle grow with fert. but a whole lot cheaper.

Once I transplant into real soil, then I don't fertilize for abotu 7 to ten days. The reason behidn this , is that as soon as those seedlings hit real dirt they start putting out new root growth and feeder roots and if you put a bunch of liquid fert on them right away you take a chance of burnign the new little roots that are emerging. They need that week to liek harden themselves off.

Starlight -

When you transplant your seedlings from the soilless mix into something else, what kind of soil do you transplant to? Must I use a transplant soil which I've seen for sale in catalogues, or can I transplant directly to Miracle Grow (or Jungle Soil)?

Thanks for the great info on when to / not to fertilize the baby seedlings!

You cna use Miracle grow or Jungle Grow. I prefer the Jungle Grow. Not only is it cheaper but a percentage of sale s goe s to the wildlife life foudnation to save endangered animals, but Lowe's may be a bit father for you to drive.

Stuff in catalogs is hype , most of it.


The reason behidn using the soiless mix to start with is to help cut down on the fungal diseases and give the seeds root a chance to develop without havign to deal with posible infection from the soil right off the bat.

Great, thanks!

XMelissaX,
I'm curious about the size of the pots you are using since you don't need to transplant. Right now, I am struggling with the sizes that I have been using for the last two years, and considering starting seeds in larger containers.

We start our seeds in 1" x 1" rockwool cubes and then after they have sprouted we put them under daylight cfl bulbs. We transplant into coir with epsoma total fertilizer at different levels in a 16oz plastic cup. It is working pretty good for us. Didn't mean to but in.-----------G

I use the 72 cell trays for most veggies/annuals. Larger plants I start in whatever random trays/pots I saved from years before. I grow under fluorescent lights, so they usually don't get to a point that they have to be transplanted. My personal opinion, unless the seedling is really suffering from being root bound it's really not necessary to pot-up. They grow so quickly once planted in the ground, I don't think it really benefits the seedling to adjust to being repotted a couple times before getting a permanent home. Not to mention all the work it'd take to replant 600+ seedlings...

Wow thanks everyone for all this great advice, I'm starting seeds for Cleome, Nigella, Zinnia, Monarda, and Agastache. The Nigella and Zinnia I'll start in individual tiny pots as I've heard they don't tolerate having their roots disturbed. The others, which are less sensitive, will be started in flats or grouped in larger pots, depending on what I've got laying around.

jasperj
I owned and operated a commercial greenhouse in NE during the '80's. I sold houseplants, vegetable plants, and hardy perennials suitable for NE climate, including succulents. To keep plant prices competitive, I mixed my own potting soil. Plants don't care what they grow in or we would have spread Miracle-Gro mix throughout our garden. The only criteria is that the soil is well drained, friable, loose so tiny roots can penetrate. Also that it stays moist for a reasonable amount of time. Plants will grow in plain vermiculite with plant food added--liquid or granulates.

I bought bags of peatmoss, vermiculite, perlite, and sand. My basic mix was peatmoss (pre-moistened first), and vermiculite in 1:1 ratio. If a plant needed more drainage, or a soil that needed to dry out quicker, such as succulents, I added either sand or perlite. I used my basic mix for rooting cuttings also. I used my wheelbarrel to mix it, then stored the basic mix in a large garbage bin with wheels. When I potted up a plant with the mix, I added plant food granulates, which is usually good for 6 weeks, depending on the brand. This mix makes the pot light in weight. It is much cheaper to mix your own if you have many plants, rather than buy pre-mixed. Another bonus is that it is sterile.

When the, so called, "professional mixes" came out on the market years ago, the ingredients was very similar to my basic mix.

I sprout seeds in moist kitchen paper napkins. As they sprout and develop tiny roots, I move them into flats, spacing 1" apart. From there, I transplant them after the first set of true leaves, into 6-packs. Some I pot directly into 6-packs, depending on how long their roots were. This way I know just how many plants I have of each, since I only want 12 of each. Each pot is about 1-1/2" square. Walmart carries a flat with 12, 6-packs, which is what I use. They can remain in these small pots for quite awhile. The flat of 6-packs fit nicely under lights. You don't want to overpot them, the next size up would be 3" sq. or round, max, if needed. Roots needs room to grow, but too big a pot with too much moisture that the roots can't use, is inviting rot.

CAPTION: A flat of 6-packs with hardy perennials sprouted in moist kitchen towels. These were ready for the 6-packs, rather than in flats.