You don't mention where you garden, but I take it you get freezing weather outdoors in winter, so can't grow them outside? I would suggest that you give them as much direct light as possible, and leave them in a community pot for the first year. They would typically start blooming in a USDA zone 9/10 climate by mid March or as late as mid April here in California conditions. They are perfectly fine with cool growing conditions that may even dip down to near freezing, but are probably not as hardy to cold conditions when being grown in USDA zones colder than 9b, so would prefer temps no lower than 40~45F if grown indoors, and even better if lows are around 50~55F. The foliage will tend to get etiolated if not given maximum light possible when being grown indoors, and a cool greenhouse is probably a better location than a windowsill for best growth. I doubt they will bloom before the second year, maybe even 3rd year for you outside a Mediterranean climate zone. Keep watered and actively growing until about late May, then allow them to go dormant and keep dry over the summer. Start watering the pot again in late September or early October when they will naturally tend to wake up. If the community pot is too small for all the seedlings, simply move all of them as one clump into a larger pot, but no need to separate them yet, as they naturally tend to grow as thick clumps without problems. They really are an easy South African bulb to grow as long as you don't rot them out in summer with unwanted moisture.

If you collected your seeds from someone who lives in your area - and their plants were growing outside - you can be reasonably sure that Sparaxis is either fully hardy or marginal hardy in your area.

Sparaxis grow with winter rain - and are frost-hardy in zone 9a.

They can be naturalised in short turf on a sunny and free-draining slope. Or as ribbons in sunny garden beds.

They produce bulbils on their stems as well as underground.

While they prefer good sunlight some will also flower in semi-shade under deciduous trees.

Totally agree with the recommendation to pot on your clump. Check the bottom of the pot and, if there are roots escaping move up at least two sizes - but not so they're an island in a sea of brown mix. Allow about two inches all round. My own preference would be for a half pot rather than a full depth.

Some Sparaxis will flower the year after they've been sown. For others you might have to wait for the second year.

If, after you've grown them on steadily over this winter, with light feeding and good light, they look to be healthy and vigorous you could probably separate your clump in August or September.

If you do plant them out in the garden you may find that they end up on the top of the soil at the end of the growing season. Replant what you need as you need. It's a good time for reducing the numbers so as to get a less crowded display.

For the Watsonia - unless you get dry summers you might need to keep this one in a biggish pot as it gets older just so you can give it the summer baking it needs, plus the heavy soil mix - and the winter rain. (On the other hand - it mught be one of those darned bulbs that have never read the garden books!!!)

I'm always highly suspicious of Watsonia, as several have a tendency to weediness in the garden. However, this one is beautiful and I hope you succeed with it.