What kind of seedlings are these?

Just a couple of suggestions: (1) make sure the drain holes are close to the cup edges. I usually punch them right on the bottom edge so they can drain from both the sides and the bottom. Eliminates the small pools of water that can be trapped otherwise.

(2) Transplant your plants deeply into the new containers. An 18 oz. cup is a lot of soil for a small transplant seedling, much more than it needs, and they don't need to be sitting right up at the rim.

Depending on the type of plant (ie: tomatoes and peppers) you can only fill 1/2 the cup, insert the plant and then fill up the cup as it grows - up to just below the bottom set of leaves. You can even bury the bottom set (the seed leaves or cotyledons). With non-woody-stem seedlings like clumps of flowers or leafy greens, deeper in the cup helps support the plant and keep it from falling over at the soil line as it grows.

In other words, try to avoid the itty-bitty-seedling sitting on top of a great big cup of dirt look. ;)

Dave

Next year, transplant your seedlings into a coarser potting mix...like what you'd use for house plants. The germination medium is so fine textured and slow to drain. Root systems don't like that.

It's also a difficult planting medium to water. Be very cautious about over watering (which means too often). If you use a very porous medium, over watering problems often become a thing of the past.

To help with watering, I started a thread 'help with watering' that is a few posts down on this page.

Because your seedlngs are so small they won't go through teh transplant shock you are thinking of when you plant them in the Spring. So they do not need to be 'soaked' to make it. Watering is tricky until you get a system down. My plants look VERY dry before I bottom water. You can fix under-watering but you really can't fix over-watering. The soil will get dry and crusty on top before I water but I still hold off untill my pots are 3/4 dry and then let them bottom drink until the top soil gets wet.

I hope that helps.

Keriann~

Dave - these are broccoli seedlings, but I'll have some cauliflower and parsley in about a week or so that I'll need to transplant, too.

My seedling is probably about 3-4 inches tall and looks really healthy and strong (so far!)

Should I switch it into more of a potting mix? The germination mix seems very light and dry to begin with. Even when I watered last night, the soil never seemed to be uniformly wet (or moist). I guess part of my concern is that I've never used a medium like this before, so it's hard for me to tell if my plant is getting enough water.

Thanks for everyone's replies!

For the seedlings you listed I wouldn't use a cup nearly that big. Save those big cups for things like tomatoes. An 8 oz cup would be plenty for them - foam coffee cups work fine. And it doesn't need to be filled to the brim either - 3/4 full is fine.

And I agree with everything rhizo and keriann posted plus I also should have mentioned that you need to wet any mix you use BEFORE you put it in the container. Pre-soak it in water and then wring it out in your hand.

Dave

I agree too--
That's how I transplant Dave:

I mix my promix with water in a tinfoil roast pan until I can pick up a handfull and squeeze and just a little water comes out. If too much water comes out I add more promix. That way I know the soil is wet right through but not too wet.

Thank you so much - you are all very helpful!

I will mix my soil with water until it's the right moisture content, then move my seedling to a smaller cup.

One more question, will this cup be a sufficient size before I plant my seedlings outside in about a month, or will I need to transplant one more time?

Another month? Ahh started the old broccoli and cauliflower way too soon, huh? ;)

Well the parsley will be ok since you can always pinch it back some. The other two may need to be transplanted yet again depending on your growing conditions. The cooler (60F or less) you can keep them the slower they will grow so avoid letting them sit around in warm (70F) air and don't feed them and go very easy on the water. They need to be stalled a bit. And try to get them into the garden ASAP even if it means you have to cover to protect them from frost. Both are semi-hardy so will tolerate cold, just not hard freeze.

Dave

There should be no need to "plant up" again. Once the seedling sets out, you may want to give the seedlings a diluted fertilizer. There are plenty of guidelines for exactly how dilute you want it...basically a 10:1 ratio to start would be plenty of "food" for the seedling. (10 parts water to 1 part regular strength fertilizer).

Personally, I use a kelp spray and do a foliar feeding once a week, with the kelp spray at about 1/2 strength. (probably more than my plants need, but they haven't complained yet!)

This is my first time ever starting seeds so it's a learning process all around.

My gardening info says to start broccoli seeds 12 weeks before the last spring frost, and then the earliest to plant outdoors should be 5 weeks before the last frost.

My average last frost date is May 7, so I started the broccoli Feb. 13, and will put them out April 3. Am I missing something?

Not missing anything but I would question the info source. The average on all cole crops is 6 weeks before transplanting, 8 weeks max. Small, younger transplants tolerate the stress of transplanting much better than older, larger ones do.

Dave

Thanks for your help Dave.

My seedlings will be 7 weeks old when I transplant them into the garden, so they should be good.

I really appreciate everyone's patience with my completely inexperienced questions!