Nerine sariniensis entering summer dormancy
This last weekend in May, which is a three-day holiday in America – Memorial Day- marks the start of summer for many. At the very least, it is the weekend old-timer traditionally plant out tomatoes and cucumbers, red geraniums and cemetery plots. For plant geeks and enthusiasts who are obsessed with growing highly unusual plants, this time of this year means that a good half of our collections are starting to enter a dormancy, triggered by the lengthening days, hot temperatures and dry conditions.
Many plants and bulbs that grow in climates like South Africa and Patagonia are designed by nature to go dormant when it becomes hot and dry. Any plant that has a specialized water storage capability can survive through a hot arid summer, these plants are collectively and botanically known as geophytes, and many geophytes from arid areas have adapted their growing and blooming season around the climate, hence, they grow and bloom during the African rainy season, and slip into the safety of semi or complete dormancy during the hot sunny dry season
Nerine sarniensis in bloom in November
This Memorial Day weekend starts the dry season in my greenhouse, most of the bulbs that have been growing blooming all winter, are either finishing up blooming, or have set seed and are already dormant. This weekend involves the final collecting of seed, the cleaning of pots, and the restaging of plants. Collections of potted bulbous Oxalis, Marine species, Tecophilaea, Narcissus romieuxii et al, Lachenalia, Romeulea, Velthiemia, Fritillaries and Cyclamen species all are relocated to dry areas of the greenhouse. Each of these species requires slightly different attention throughout the summer, but on the whole, they remain mostly dry and some even bake in the sun bone dry.
There are other bulbs that go dormant for the summer, and many of these come from North Africa, the Mediterranean, Greece, Turkey, and South America. Think about it. Even in the garden, many of your spring blooming bulbs like crocus, Narcissus and the like, have bloomed, grown foliage and have disappeared underground until next spring, by the time early July comes around. Indeed, most bulbs like this cycle, and prefer to be dry and dormant during the summer.
The rare blue Chilean Tecophilaea cyanocrocus
Tecophilaea cyanocrocus, the rare Blue bulb from South America once extinct in its habitat, but recent reports state otherwise, these Tecophilaea also need dry summer treatment, and their pots are allowed to dry out as they plant begins to yellow. They remain dormant until September.
Tecophilaea are slow to divide; yet they do divide for some growers. Growing them from seed makes the most sense for those who are more capable, and since bulbs, when one can find them, sell for $15. 00 to $25.00 and up, and a decent potful may require a second mortgage. Don’t let that put you off; clearly a single bulb is just as exciting, and a fine way to start off a collection.
A pot of Narcissus romieuxii in November
Speaking of seed, the very best way to get the winter blooming dwarf narcissus known as the Bulbocodium type (N. romieuxii, N. albidus and the like) to fill a pot, is to grow them from seed. The plants that have bloomed all winter are now looking pretty ratty, as they yellow and die, but the many seedpods are all saved, and sown immediately, deep in pots, but not watered until we start the fall watering again in Sept. The theory is that once sown deeply, the little moisture in the soil protects the bulb seed from desiccating too much, perhaps mimicking what actually happened high in the Atlas Mountains of Morocco where they grow. Deep in their seed pot, the bulb seed rests all summer cool and deep in thier pot and the hot dry sun pounds on the surface. When the fall rains come, in September, and the cooler temperatures, they can start growing, triggered by nature.
Collecting seeds from N. romieuxii
Narcissus romieuxii seed is small, and yet sturdy. Plant the seed now at the time of harvesting, but keep the pots dry until autumn, then begin watering. These tender Narcissus can only be grown in frost free areas, or ideally in a col greenhouse or Alpine house throughout the winter. Nerine sarniensis too are put away dry, in their pots, for a vacation. Although the Nerine enjoy an occasional splash or have water as most plants in the Amaryllis family do while dormant. The last thing they want to do is shrivel, and their roots really never go dormant. Just knock a Nerine out of its pot in August, and you will see how fresh their fleshy roots look. The few people who grow these in North America have all connected on-line, and many of us believe that a little water may help during their summer rest.
A pot of seed pods split and ready
With these seed maturing daily, I must carefully check each morning to collect the seed as the pods split. The seeds are saved in little cups and then I pot them in a fast draining soil, relatively quickly, planting them deep, nearly 3/4’s of the way down in a small pot,sowing them rather thickly. It is important not to water them at all however, until September 1st or so, when watering starts for thier parents and all of the summer dormant bulbs. This best mimics tha autumn rains along with the cooler night temperatures and shorter days, all of which stimulate the bulbs that have been dormant all summer to start growing in the greenhouse, where they can bloom in the winter months. I ahev found that the seeds of many bulbous plants respond best this way, a fien and handy tip taught to me by Ian Young, President of the Scottish Rock Garden Society who grows a large collection of Narcissus of this type.
Cyclamen species are similar, also requiring a summer rest that is dryer, but they are just starting to go dormant, so more on those later!
