Arisaema Planting Guide
Arresting Arisaema – Spectacular Serpents!
Rearing up from the woodland floor, wing-like leaf spread high above, the fantastical blooms of arisaema flare like the hood of the cobras for which they are named. Native to woodland settings, Arisaema thrive in well drained soils rich in nutrients, with dappled sunshine overhead. Whether you are planting just a few to make a striking architectural statement, or are planning an extensive grouping, be assured that these winged cobras will form a breath-taking focus for your garden.
Don't you need to plant a spectacular serpent to complete your own corner of Eden?
Sun ExposureCool, dappled shade under a spreading canopy of trees is ideal for growing arisaema. However, the north or east side of a building, that protects them from all day sun and heat will work as well.
Soil TypeWhile arisamea can and do thrive in an astonishing array of countries and elevations, it is critical to get the specific conditions right for them to flourish in your garden. The soil must be moist but not wet, with excellent drainage to ensure the tubers and roots do not rot. Arisaema are highly prone to rot in poorly drained conditions. The soil should also be porous – with plenty of air spaces. Work the soil well to break up any compacted areas, and incorporate leaf mold, compost and perlite to improve both the nutrition and structure of the soil. Raised beds or small hillocks will also help you to achieve the level of drainage so important for happy cobra lilies.
While fussy about their drainage, arisaema will grow equally well in acidic or alkaline soils.
Planting DepthPlant arisaema tubers 4-6 inches deep, to give them a good opportunity to develop a healthy network of roots, and to protect from cold in the lower zones of their hardiness range.
WateringArisaema should be kept lightly moist, but not wet. Excellent drainage is critical to ensuring your tubers do not rot. Water in the evenings with a sprinkler or watering can when the soil is dry. A fun trick to help you in aiming for just enough, but not too much water, is to over plant your cobra lilies with achimenes tubers. When the achimenes wilt, it is time to water your arisaema. When the achimenes are lush and happy, your cobra lilies will be too. It is not necessary to water while the arisaema is dormant.
FeedingArisaema are heavy feeders, and will benefit from both a time release granular fertilizer worked into the top soil each spring as well as a periodic feeding during active growth with a water soluble fertilizer or seaweed extract.
Winter CareThis is critical - Arisaema must be kept quite dry during their winter dormancy! When planted within their hardiness zones, arisaema can remain in the ground, undisturbed over the winter if you protect them from rainfall. A thick mulch of compost, leaf mold and dried grass clippings or dead leaves will provide excellent insulation as well as feeding the soil for the coming spring. Where the winter chill is severe, carefully dig the arisaema tubers, and allow to air dry just a couple of days. Then store as if planting them in pots, using a rich, soilless mix. Store cool, dark and open to air circulation. Dampen the soil mix very lightly on a monthly basis until you are ready to re-plant the following spring. Be sure to protect tender new growth from a hard frost.
As stated above, arisaema are prone to rot. This bears repeating. Take great care to provide loose soil that drains well, and do not over water. Once you are able to create the right conditions, arisaema are easy and fast to grow. They may take more maintenance and preparation than other plants – but the drama of success is worth it! Enjoy!