I've found the most common types of seeds most people have trouble germinating are varieties that need light, and juggling that awkward line to keep them from being buried but not drying out. So here's my top tips to get those tricky light lovers up and at 'em for you.
Store seeds in the fridge
First things first though, fresh seeds = better germination, so store your seeds in the fridge for maximum freshness! I've found storing my seeds in the fridge (in ziplock bags like the ones we send all our orders in), my seeds last a very long time, and I swear it helps their germination rates be their best selves too! I try to have all seeds in the fridge for about 2 weeks before I need to sow them.
Sow light lovers in a dibble
Seeds that need light to germinate used to be my hardest types of seed to germinate, as sown on the surface without proper covering, they're just a few hours of sun away from potentially drying and and dying before they really even look like they're growing. Inadvertently through using soil blocks (& their pre-made deep dibbles), I have discovered that those deep dibbles are total game changers for light loving seeds! The bottom of the dibbles are the perfect slightly shaded, still light mini microclimate perfectly forgiving for seed starting, as it doesn't dry out down there half as fast as the top surface does. Nobody has time to hover over seeds all day, so save yourself a little anxiety and just make sure to sow in deep dibbles (1-2cm deep depending on your cell size).
Vermiculite is an expanded natural mineral that is fantastic at retaining moisture, while also still letting some light through. So a little dusting over seeds that need some light to germinate, is another trick to maintain that critical moisture needed for germination, and buy you just a little more time so you don't have to hover over them all day long.
Use a dome (of sorts)
Whether you use a traditional tray & dome set up or something similar (like trays in a large clear plastic tub with a lid ajar), maintaining a high humidity environment is a godsend for faster, reliable and consistent germination. But do make sure you leave a little ventilation as zero air flow does equal fungal issues.
It's total murphy's law that all the light loving seeds are all so tiny, so bottom watering is the only sure-fire way to water them with out risking burying them in the soil from overhead watering (once they're buried it's too dark for the light loving seeds to germinate). Bottom watering also helps keep the tiny seedlings dry and can help avoid fungal issues, so I'd recommend watering all your seedlings this way until they're much bigger and ready to handle a harder life. To bottom water simply place your seed tray in a larger waterproof tray (make sure not to overfill and risk flooding the top of your cell trays), and leave to soak up from the bottom up till the top is wet - then remove cell tray from the watertray (trays left in standing water for too long will end up with fungal/algae issues).
I bought some of your beautiful seeds recently which I am looking forward to trying.
You mention the soil blocker which I am keen to try, I am just wondering if you were able to buy this in NZ as I haven’t seen any available here, I have seen them on AliExpress but was hoping to avoid the long delay in the post.