You might need to be a little wary of purchasing waterlilies. Some varieties are very well behaved, spread at the predictable pace of a foot per year at most and do not produce a brutally large knot of many crowns.
Many of the hardy hybrids have the 'choice' features of prolific flowering, with modest spreading habit.
Some of the hardy hybrids are brutes... Attraction and Colorado come to mind. They might make a dozen crowns a year and produce a massive large knot of rhisomes.
Thats a lot of crowns and a massive knot of rhisomes in four years, one year 12, year two 144, year three 1,728, year four may be Lake Woebegone and a titanic knot of stuff a team of wrestlers with chain saws could not sort out
Waterlilies at the cheap end of the market tend to be invasive brutes, where folk are desperate to get rid of them. Expect them to be found at Walmarts and ebay at rock bottom prices...
The native hardies can be bad news, odoratas may spread fifteen feet a year when they get going
Any lily grower who knows their stuff will steer you toward the more suitable varieties that are robust enough for native plantings but present a more reliable growing rate.
The only snag being of course, the availability of sedate well behaved varieties is quite different to the availability and price of the brutes...
Regards, andy
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