I almost always plant nasturtiums in containers and use a standard potting mix for that purpose (in my case, the 5-1-1 mix). Since there are virtually no nutrients in potting soil - unless added by the manufacturer - the seeds germinate well and grow fine. It is my understanding and experience that it is fertilization or an overly enriched soil that can cause issues, typically encouraging a lot of lush foliar growth at the expense of flowers.

@gardengal48 (PNW Z8/9) How many nasturtiums would you keep in a 14” basket?

I plant nasts all over. All parts of the plant are tasty and it's pretty. The ones out in the poorer parts of the garden do well, and so do the ones in my containers. Including hanging baskets. I could keep 4-5 nasts trailing out and something in the middle- usualy something taller like chives or basil. Sometimes other flowers. Can't say I've had a huge difference in foliage or flowering between out in the gardens or in the baskets. I am not always awesome at keeping up with watering baskets as they should, so that always hurts all the plants. But when I keep them watered right they are lovely cascading out of a basket. Or raised bed :)

With the kinds you have they are a bit tall for just center- they will prone over a bit as they mature. So around the outside. But they will just prone over, they won't cascade. So if you want someting to cascade too, I'd limit the nasts to 3, maybe 4 if you don't do a center and then the alternate spots with your cascade plants. If you want just nasts, I think you could do 4-5 since you will still get some upright with those. Maybe 5 with 1 in the middle if you are pretty serious about tending your baskets.

Mohogany makes a very dramatic pesto and a pretty vinegar if you use just the flowers. The leaves of both go gorgeous with fennel greens and basil or cilantro to make pesto. The seeds young of both kinds are good as capers, too.

Excellent insight, @beesneeds. I have a few Black-Eyed Susan vine ‘Spanish Eyes’ seedlings that I‘d like to use. My plan was to have them climb my birdfeeder stand with the nasturtium baskets occupuing two of the stands hooks. This may not be viable because the baffle has to stay for the squirrels and I don’t have a plan for that. Might look awkward, which is not what I’m going for.

Do you all think the nasturtiums would still look off without a spiller, but with the Black-Eyed Susan vines climbing from the ground? And them to the baskets? Use the vibes elsewhere? I am not opposed to putting the vines elsewhere (I have a spot) and getting something else to fill out the baskets.

What would you do? I like to experiment, but failing a lot gets old. I planted several hundred crocus bulbs in my fairy garden and the squirrells have ruined all but one and I’m pretty sore about that right now— looking for a win :)

Speaking of nasturtiums, anyone in the Boston area should go see the fabulous display in the courtyard of the Isabel Gardiner Museum next month! I’ll be making a special trip from New York for it.

I wouldn't put black eyed susan vines with nasturtums in 14". The vines would distract and they are more likely to edge out nasts in needs and growth habit.

At that height and the window with the kinds of nasts you have I'm not sure you really need much cascade. From the window and ground the 10-12" should look good. I think doing a nast in center of the ring would look great there.

I really appreciate the insight all, thanks!

Kitasi2 Can you post some pics here? I'd love to see them.