I made a similar post a few years ago and got a little grief, so this is with advance apology to anyone that disagrees. It is just my own belief and has served me quite well through the years.

These are my opinions that I formed and firmed up after reading a doctoral thesis / dissertation on the Reproduction of Crappie. If I could find the original I would scan it and post it up. I had the paper copy. I had contact with the author sharing what I had witnessed during my many working dives. I have made hundreds of scuba dives witnessing the behavior as well as owning a small lake outside my kitchen door where I had coffee every morning watching " my little buddies " all year long for 18 years.

They will spawn, they don't really have much of a choice. They can retain eggs until they are milk, but while we have all seen that throughout the years, it is rare and usually follows a season/year of back to back minor fronts and weather extremeties , but seldom including low water.

Crappie eggs are sticky and usually deposited on anything vertical that appears to be stable enough at the right depth. The depth is dictated by light penetration given the right temperature range and daylight hours. They will lay/deposit eggs on the side of an aluminum pontoon moored in a slip even. There are deposits on almost every shaded side of the Styrofoam flotation blocks supporting marinas.

They will deposit on fresh green growth but not dead winter stalks of reeds. The more dead of obstructive growth there is the more desirable the location but the primary material needs to be strong enough to weather waves and agitation of weather events.

They will not deposit on, or in mud. What a lot of people say are beds are just the males cleaning the mud away to find a suitable underlayment. "Cleaning the gravel" if you will. The males will do this cleaning to the Styrofoam block or side of pilings they are prepping. They will brush algae away from foam or wood pilings before the female will lay. Their tails will look worn like bass that has been fanning gravel for two days.

The water clarity dictates the light penetration from the sun, the structure surrounding dictates the directness of the light, and paths of shadows moving during the day.

Most all types of larvae represent a threat to the eggs while still in clutch so any bait that has legs or feelers is prone to get hit anywhere near a clutch of eggs. Regular jigs obviously work great, but undersell the importance of "legs" advancing the aggressiveness of the hit. Part feeding and part defense.

Colors??? Crappie see more in gray scale than in color, but that doesn't mean that chartreuse doesn't look different than root beer to them. They have very high resolution vision allowing them to define shapes in very murky water and see in many shades of gray. subtle color changes do show to them. I will always spend a minute deciding which color I am going to use and why. Here is an excerpt typical of what you see if you Google " can crappie see color? Just pay attention to the scientists and not the crappie forums:-)

The quote" Many kinds
of fish can actually see color. Some
can see at least 24 different shades of
color.
Night feeders such as walleye
and crappie trade good color vision
for the ability to see well when there
is not much light. "

Like I said, just my opinion and I could be wrong. Phill