Winter is coming. It is time for the annual hibernation to begin. Squirrels bury the last few nuts to last through the winter. Bears head off for their long naps, gardeners curl up in their blankets, waiting for the arrival of seed catalogs as their very early sign of spring.
At Hudson Valley Vertical Farms, the winter is no time for rest. There are CSA members to feed through the winter months. Despite the freezes and flurries, things are always growing with the benefit of several indoor vertical aeroponic growing systems that were conceptualized by the farm and designed and built by Aero, Rethinking Growth. Hudson Valley Vertical Farms, Inc. is a member of Rondout Valley Growers Association and Stick to Local Farms. It shares some helpful tips from its chances and mistakes made over the years from germination to harvest.
Successful indoor growing starts with the seeds. Heirloom and organic varieties that have a high germination rate of over 90% rate are a good beginning.
The farm chooses seeds from the Hudson Valley Seed Library, because they are locally sourced. The Hudson Valley Seed Library also supports affiliated programs, including the artists who design their seed packets.
The weakest link for any growing cycle is germination. This is the two-week period that starts when we plant the seeds in rock wool and add water. A growing mat and thermostat is used for germinating seedlings at their ideal temperature.
When they sprout, plants growing in an inert medium that provides no nutrition require food, light, and wind. The sooner these three elements are added, the more successful the growth will be later. An ideal electrical conductivity reading for seedlings is 0.8, half of the amount of food that is needed for full-sized plants.
The seedlings don’t need just air, they need moving air. They may grow just fine with the nutrients they need from light, water, and air, but indoor plants are weaker than their outdoor cousins because they don’t get blown around. The wind helps the plants’ resilience on a cellular level, helping them grow stalky and bushy. So once the plants' sprout, run a small fan on them for their first two weeks to simulate the blowing of the wind outdoors.
Temperature is another key ingredient. For hydroponic growing, the ideal water temperature is approximately 70°F, which can be adjusted with a simple aquarium heater. Within a couple of weeks, we transfer the seedlings from their trays over to the aeroponic vertical columns where they will complete their growing. The plants’ roots growing out of the rock wool are constantly bathed with water and nutrients, which helps the plants grow faster and fuller than by regular gardening methods. These vertical aeroponic structures contain no soil, eliminating the need for weeding and cutting down greatly on pests.
As for lighting, it all depends on the daily light needs of the plant. While house plants grow happily in a sunny windowsill (and some of them need less than that), produce being grown indoors will need varying levels of supplemental lighting.
Herbs need those windowsills, too, but a simple lamp with a grow light will give an extra boost.
Lettuces will flourish with a fluorescent light placed about one foot away from the plant, and we run them on timers for 13 hours a day (or night, when the off-peak power is cheaper). If window light is available, we set timers to turn on our lights for four hours in the early morning and four hours in the last evening.
Flowering and fruiting plants usually need a high-pressure sodium light for about 13 hours a day to produce fruit due to the thicker cell wall of fruiting plants.
Winter may have frozen the parasites and pestilence outdoors, but that ADT home protection sign is not going to keep wee beasties from trying to get your produce. Insects and fungus are the most common culprits to bring your indoor growing season to an early end.
Powdery mildew is often due to a combination of overwatering and a deficiency of beneficial microbes. Microbes in Foliar Pack enjoy eating downy mildew, a natural fungicide that works very well and causes no cellular damage to the plants while increasing nitrogen pick-up as a bonus! Many organic growers on a commercial scale employ hungry lady bugs to feast upon aphids, but they are not always the best solution for the small scale indoor grower due to their tendency to wander and get “lazy” over the winter months. Thus,we are excited about microbial helpers for organic pest management.
If hydroponics seems like something you are not ready for, sprouting using soil trays may be your indoor growing match. Sprouting sunflower seeds and wheat grass in grow trays is a simple process of soaking and spouting the seeds in mason jars followed by patting the seeds on top of a grow tray of damp soil and simply adding sunlight from a sunny window. Sunflower sprouts are a plant-based source of protein and are easy to cut and toss onto your salad or enjoy as a snack.
So, there really is no need to wait for the ground to thaw. The indoor gardener can look forward to thick bunches of herbs and fresh, flavorful lettuce over the long winter.