The seasons march on, and this time of year I am thinking constantly of what lies ahead: seed sowing the Mediterranean species; reorganizing the greenhouses; repotting most of the bulbs and getting ready for winter in general. Autumn is the busiest season as far as bulb care is concerned, since the Mediterranean climate bulbs must all be repotted before they start to grow around the end of October to the middle of November. A few can wait a bit longer, and during the same time period seed must be sown of most species. Some bulbs multiply, but others, like Calochortus, must be sown every fall, and it is a very big job.
In preparation for the tasks ahead, I am completely reorganizing my Mediterreanean greenhouse and having benches made. In the past I have had all the pots on the floor. This was largely due to the expense involved of buying or making benches, but now I am happy to say that I am able to invest the needed money. This is helped by a new product, a plastic bench top that is light weight, easy to clean and relatively inexpensive. Before now greenhouse benches were made of metal, so they were very heavy, very expensive and would degrade over time. The new bench tops are UV stable, and should last a long time. Here above I am in the process of moving every single pot twice, fist off the floor and out of the way as each bench is brought in, then organizing them alphabetically on the benches (and still smiling!). I won't trust anyone else to move them, since they must be kept striclty organized or I simply can't find things. Even so, as I put Calochortus plummerae in place, I will inevitably stumble across a couple of pots of C. bruneaunis that I overlooked, necessitating moving them all again. Arrrgh!
Mark and Shawn, seen here, have also put a new ventilation system in, and now the greenhouses are vented automatically, keeping the temperature well below 85F even on warm sunny days. Both the new benches and the new ventilation system are intended to make my work easier and more efficient, and, hopefully, to reduce losses. The problem I have had with the pots on the floor is inadequate drainage, with the bottom layer of potting medium not drying out completely in the bulbs' summer dormancy. Summer dormant bulbs need to be kept completely dry during their dormancy, so any excess moisture can encourage rotting. I am expecting that elevating the pots off the ground will improve things considerably with better drainage, better air circulation and easier access.
It is finally warming up in Humboldt County, after an extremely cold spring with snow flurries in April -- very unusual for us. My greenhouses are not heated in winter, and other than fans, there is no cooling system. One of the problems with our foggy climate is that temperatures in the greenhouses can swing more than 50 degrees F. in 24 hours, heating up on the sunny days, and cooling at night. This is a bit extreme, even for bulbs. Most of the bulbs I grow come from climates where the temperatures reach 100F at least, but growing them in black plastic pots is another thing entirely, since the soil temperature in a pot can get much higher than the soil temperature would be in their natural environment. In the wild, bulbs often grow at great depth, escaping the scorching temperatures on the surface. In a greenhouse, we have to take some steps to moderate the temperature.
hading in a greenhouse is more effective if you can put the shade fabric on the outside of the structure, but in this windy climate this is impossible. Aluminet is more expensive than traditional shade fabric, but it has other attributes that make it worth the expense. It is feather light, and can be suspended by clips from the frame of the greenhouse. Because is is metallic and shiny, it reflects the light. I bought 40% shade fabric, and was worried about it reducing the light intensity, especially on our frequent foggy days. It doesn't seem to do that at all, in spite of the 40% rating. Another bonus is that the fabric itself doesn't heat up, unlike black plastic shade cloth, and you can place it directly on top of the pots, as I have done, on some seedling pots that are going dormant. The bulbs, at this stage, are tiny and are in the top one or two inches of potting mix, so they can desiccate if they get too hot. In their natural environment they would probably be shielded by drying grasses or adjacent vegetation.