Tips for growing Butterfly Ranunculus

Pre-sprouting ranunculus is a fairly straightforward process but there are always a few hiccups that can happen along the way if simple and easy mistakes are made. For butterfly ranunculus, the list of mistakes is slightly longer as these corms are even more prone to rot and take longer to sprout than the more widespread varieties. Thats not to say, however, that they are any less worth the struggle!

Butterfly Ranunuclus are like a regular Italian Ranunculus on steroids. They grow 50% larger (including the root size) and with a bounty of more blooms! Soaring past 2 feet in height, these beauties will shoot up 4-5 large stems that each will produce a spray of 10-12 airy single blooms that look like floating butterflies in the air. They are not at all like the compact buttercups of a classic Italian ranunculus. If you are looking for a full breakdown of the pre-sprouting process, you can find it here. For special tips on butterfly varieties, here are a few key differences to keep in mind when starting them:

Temperature

Butterfly Ranunculus are less cold hardy than the others, being affected by even -1 degrees Celsius and requiring covering if temps drop below this. With that, the temperature for pre-sprouting is also higher! After some trial and error and over a month in a cool garage of 4 degrees awaiting sprouts, we have found that a fast track to roots is to pre-sprout these corms in 10-18 degrees Celsius instead. This simple change made a big difference and we have been pre-sprouting the rest of the corms in 18 degree temperature with much more success!

Moisture

Because ranunculus corms are soaked to bring them out of dormancy, they are full of water to supply new life. This means that moisture from the soil is almost unnecessary except for deterring them from drying out again. This happens quickly however if the corms are left out of the soil after soaking or sitting in completely dried dirt. If this happens you can kill the corms or make their sprouting uneven and sporadic.

Our method is to lightly soak the soil and then make sure that there is a full 2 inches of promix covering the tops AND bottom of the corms. Instead of our standard 6 cell trays that we use individually with other ranunculus, we potted all of the butterfly corms together and compressed the dirt around each to remove the air pockets that result in soil losing moisture more quickly. Within 3 weeks and with our temperature increase and maintainted moisture levels we were able to find new roots growing!

Rotting

While rot is almost always a bad sign for corms (especially Anemones which typically die quickly once rot is present), there has been so much blue fuzzy rot on the bottoms of the majority of the corms we started this year. To our surprise, this has not hindered the sprouting process and almost every corm has still sprouted with nice long roots before needing transplanting!

What did we do about it?

Using a paring knife and a little bit of wild courage, the rot can be scraped off of the tiny tubers after removing the soil around and in between the bottoms of each corm. Its a little bit of a nasty task but with the price of these prized corms, its hard to just leave them. Each corm required several of the 1- 2" bulb tendrils that shoot downwards to be removed. Some were already mush and just needed scraping out while others were covered in blue rot but were still firm. These pieces were twisted to breaking and pulled off and the adjacent roots with bits of blue were scraped clean.

An important comfort is to note that the new roots a corm produce will also supply the energy for new bulbous tubers to grow above and around the existing corm head that also supplies the new life for a ranunculus plant to grow each year. This process is also how we easily multiply our stock every year with full new shoots and eyes being present on each corm during our digging up period that are then divided before drying and storing indoors for the winter.

Fertilizing

All ranunculus and anemones greatly rely on soil nutrients to produce blooms. Generous coverings of compost mixed with organic fertilizers like bone and blood meal and sea kelp meal will allow these beauties to grow to their full potential.

A full breakdown of the dig-up process will be recorded and published later this year!