The first year there was purple in the middle of the bloom. The second and third year there was yellow. Why the change?
Peacock orchids come in flower colors ranging from white to a very rich, dark maroon red.
Peacock orchids require full sunlight, at least six hours a day, although they may tolerate some afternoon shade. Soil should be mildly acidic with a pH of 6.1 to neutral 7.0. Amending soil with peat moss provides excellent drainage as well as the slightly acidic soil conditions the plant prefers. Keep soil slightly moist at all times. Most gardeners rely upon rainfall to water peacock orchids.
Many of these orchids are sold in color assortments. This may be the case in your plants.
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm
I received Peacock bulbs with an order, as a bonus, its July, can I plant them now?
Bulbs should be planted in spring for summer blooms.
You can store the bulb until next year.
This article will help you.
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm
Received bulbs,early spring but was traveling so they've been across country and back, some actually started to sprout in the bag so was wondering if they needed to dry/rest before attempting to plant.
Thank you for sending us your gardening question. Peacock orchids are part of the gladiolus family. Since you are in a zone where they can be left inground over winter, I would plant them as soon as possible. (Not sure why you gave 2 zones, the second zone they need to be lifted for winter).
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm
It is Gladiolus murielae or peacock orchid. It's marketed under several different names. You can order them through online bulb catalogs or buy them at large garden centers or big box stores in spring.
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=a454
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm
The first year they bloomed they had the purple in the bloom. Each year since they are mostly white with a little yellow. Also they only bloom once. Should they be cut down after the initial bloom?
Make sure you are allowing the foliage to die back naturally; this feeds the bulb. They only bloom once per season.
You also will need to dig these up and store in your zone.
This article has more information.
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm