One way to check the ploidy of plants such as 'Jupiter Lighthouse' is to use their pollen on diploids known to be pod fertile and on tetraploids known to be pod fertile. Say ten pollinations on each type of pod parent. Expect pods to set. Wait five weeks and count how many pods remain of the ones that were set. If the tested plant is a diploid then the diploid pod parent should have kept most of its pods and the tetraploid pod parent should have lost most of its pods. And vice versa.
If there are some doubts with the conclusion based on just counting pods then open the pods and count the seeds that look good. The pod parent with the most good seeds should indicate the ploidy of the tested plant. The pod parent with the wrong ploidy should have very few, if any, good seeds.
I do not have very hot days In my growing conditions so it is very rare for a tet x dip or dip x tet pollination to last much more than ten days here. In climates with many very hot days that may be different. My experience is much the same as Arisumi's that daylilies rarely make mistakes when making gametes and unreduced gametes are very rare, but in climates with very hot days that might be different.
