Fall and WInter are for shipping Arisaema Tubers! Order now, because by April it will be too late.
Arisaemas go dormant usually late summer and can be dug and stored dry, like a Dahlia. Each year new roots are sent out. This allows for easy (and cheaper) shipping, so we are currently offering a fall and winter sale on selected tubers while they last. So it is never too early to order your Arisaema tubers. Store them in a dark area that is consistently cool, about 40-50 degrees F until early April or until the threat of frost has past. Once planted in the ground you can almost see the stalk growing daily.
Arisaemas are fascinating plants that are mysterious and alluring. Depending on growing conditions, (if they are happy or stressed) will determine the longevity of a plant, and determine whether or not it multiplies readily. Arisaemas multiply naturally two ways, by offsets, that can be dug and moved to new locations around the garden and from seed. Since they are heavy feeders they benefit from regular additions of compost, decomposed manure or a foliar liquid feed. By keeping the bulb bulked up, will allow the plants to spend time producing offsets and flowers. Arisaemas generally start the first few years of their mature blooming life as a male, then eventually change to female. However if the tuber does not have optimal conditions they will change back to male until they have better conditions and have stored enough energy in their tuber. This keeps the tuber from spending extra energy on feeding developing seeds. Some species remain bisexual, producing both male and female flowers on the same plant.
General cultivation for Arisaemas: Plant them relatively shallow, no more than 6" but often they prefer to only be an inch below the surface. The soil needs to be rich and loose, well draining with some grittiness to it. For those who have poor draining soil, it is recommended to bring in good commercial "soil" to add on top of existing soil, mounding it up a foot or more. Each year, if possible, a thin layer of mulch or aged compost should be added on top. I use the term soil, but it should not be silty or too sandy and often the commercial soil mix is too wet and heavy with poor air circulation. I never buy without handling the soil first to check for consistency. Occasionally I even buy a five gallon bucket worth and check for porosity. That being said Arisaemas can't dry out during the summer months (while in active growth). If they dry for too long they will go dormant for year and this shortened growing season will greatly diminish their vigor for the following growing season.