Any of you had to deal with this?
I got two packets of Echinocereus seeds, hardy ones. Planted both in a plastic container, half-half.

One of the two kinds germinated nicely, the other one slower. For a long time, there was ZERO germination in one half of the container.
What I did was I kept watering.
Seeds need moisture, right?

I could see the seeds looking great, but lazy.

After a while, I saw one seed germinate, then another, and so on.
Problem is, I also got moss in the container.

DILEMMA: stop watering - the rest of the seeds won't germinate.
keep watering - will this moss hurt the little seedlings?

I have heard of this before. The moss will complete with light and food from the seedlings. Best to not have the moss in the first place. I don't have any answers. Will keep watching to see what advise you get. Good luck.
Stush

Iron sulfate, but it can kill seedlings. You could adjust ph but that will take time and might not work or be worth the effort. Try increasing light and putting a fan in the room

Thanks again Mark. So a higher PH will kill or stop moss from forming? Don't cactus like a higher PH?
Stush

Oh well... That pot is on balcony, on a table, if I brought it closer to window, it may have too much sun (although, being on North, it's kinda OK... I only have it in the morning).
And... anyway I've got quite enough seedlings of one kind, and now about 10 of the slower one.
Un-germinated seeds still visible... but I am thinking what's best for the plants I already have.
I will water less and hope the moss will go away.

@ stush - yes most moss, not all , likes acid soil. I would guess that most cactus do as well but i have never had to adjust ph either way in cactus or succulent plantings so i don't really know.

And can you cut up newspaper and wet it and try to ' smother ' the moss by making a creative weed cloth around the seedlings? Just guessing
I assume you can not manually remove it. Water less is probably your best bet and keep a good airflow and use clean tap water. Good luck

have you heard of this http://en.wikipedia.org/wiki/B...
or Cheshunt Compound its not made anymore but look at the ingredients

heck, you know i just put zinc flashing up on my roof to prevent moss, i got an idea might actually work.
Use a piece of zinc in your water bottle.

I use hydrogen peroxide to kill algae and I wonder if spraying with that would kill the moss and not harm the seedlings? Dilute it a bit and see.

Great ideas. In most information about plants. It seems they leave out the PH requirements of plants. Why I though cactus liked higher ph is unknown. Thanks for the update.

Oh I know that Bordo mix... dad sometimes used it on grapevines....
Would be too complicated to make just for a small pot of cacti
H. peroxide looks ok. I have some.
But I started watering less and I will also move it towards the window (= more sun) and hopefully the moss will just vanish!