the only problem i see ... is that you have been rather successful ... lol ... perhaps you ought not change much of anything ...

what was your seed source ??? .. the usual complaint is being ripped off by seed sellers ...

im not sure you ought not being doing a happy dance with the germ rate you got.. rather than trying to fix what might not be broken ...

interesting media mix.. how did you come up with that???

ive had success like this ... then over thought it all ... and tried to fix everything.. and then failed completely ... so again .. perhaps you ought to be happy about what you got.. and just run with it ... keep in mind.. TX aint the native range of anything you are growing .. [as far as i know] ... so some of your problems might have nothing to do with whats in the pot ... so hesitate before you start messing with the pots ....

ken

My seed source was Sheffield's seeds (you should be able to look it up pretty easily). I wanted to have enough to start my own miniature redwood forest, so I looked for somewhere I could buy bulk (I got 1000 seeds for $40). The media mix I came up with by browsing through a few forums and seeing what other people did, then adjusting it to what I had on hand.

Dawn redwood will be your least troubled, most successful species whereas giant sequoia are a waste of time for you. The dawn redwoods love warm humid rainy Summers whereas giant sequoias are super sensitive to fungal attacks and humid Summer weather is a guaranteed death sentence for them. Coast redwoods don’t like humid heat but they will usually power through albeit they get stunted. Add lots of wood chips and redwood compost when planting in the ground. I grow my sequoia family species here in Hawaii in the mountains where it’s cool and both dawn redwoods and coast redwoods thrive but the high humidity kills the giant sequoia.

Axel - what is your elevation and which island are you on? If you don't mind sharing. My understanding is that most meso-temperate/highland subtropical gardening takes place on Maui - is that correct?

By the way: Williamsburg, VA, is plenty hot and humid in summer. The 2 Sequoia sempervirens planted in the mid 1950s had reached 100' by the time they were "stunted" by Hurricane Isabel in 2003!

Add lots of wood chips and redwood compost when planting in the ground

These would be fine applied as mulch after planting but not mixed into planting hole backfill.

Microsoft Word - Planting fact sheet.doc (wsu.edu)

Just an FYI - here in Pittsburgh Dawn Redwoods grow easily and quickly. If I want a big tree fast its my go-to choice.

Dawn Reds seem to have the widest potential range in North America (in the East, from coastal Maine into Florida), Coastal Redwoods and Giant Sequoia are much more restricted in their potential range.

David, I grow conifers on the Big Island above 1600 feet. My Summer climate matches the 6000-8000 elevation conditions above Dharamshala. Winters are warmer, we only drop to the mid 50’s overnight. Not sure what’s up with giant sequoia, they seem more fungus resistant with a good cold Winter. They don’t like Coastal Norcal but they’re ok in the PNW.

Axel, you are spreading misinformation. You obviously have no idea what you are talking about. NO Giant Sequoias grow in the PNW (Pacific Northwest) as you stated above ("Not sure what’s up with giant sequoia...They don’t like Coastal Norcal but they’re ok in the PNW"). The Coast Redwood grows in the PNW, but the G.S. does not...it grows inland and only in California, and then only in the middle part of the state. The GS is not a coastal tree, and yours may be dying because of the salt air and volcanic soil of the big island, not humidity. There is practically no place on the big island which isn't within 30 miles of the ocean. https://duckduckgo.com/?q=coast+redwood+vs+giant+sequoia+map+of+where+grows&atb=v299-1&iax=images&ia=images&iai=https%3A%2F%2Fwww.savetheredwoods.org%2Fwp-content%2Fuploads%2FSORC-PR-redwood-distribution-Map-700px.jpg.

https://hoytarboretum.gardenexplorer.org/taxon-123.aspx

checking back in with our Houston friend...How are your trees doing?

roger,

According to his post less than a year after this one was posted, it wasn't going real well.

https://www.houzz.com/discussions/6167038/sequoia-dawn-and-coastal-redwood-saplings-dying

Thanks for the update! I sympathize with him. I've tried growing all the same trees in Houston. Sequoiadendron always die from fungus (too warm at night). Several varietites of coastal redwoods and my dawn redwoods have done well... but died bc of other reasons (ants, rodents, community landscapers killing with fertilizer)

Its very difficult to keep non-native plants alive.

"Its very difficult to keep non-native plants alive."

Not necessarily, many THRIVE, some too well out of their native range, and then become invasive. I am going to guess that for Houston, the non-native Metasequoia is going to do the best. The West Coast Sequoias though are going to probably have issue with Houston and its humidity. In NJ, Zone 7a/b, Dawn Reds are also the superior choice and there are huge specimens all over the place. Going to guess that Giant Sequoia would also go into decline here eventually, Summers are too humid here as well. Coast Redwoods? I have no idea, but their native range climate is sooo different, but who knows. I am growing Monkey Puzzle (Araucana araucaria) now, into year 3, and it is doing just fine. Who knows?

Metasequoia in NJ, planted form a tiny twig ob eBay.