It’s raining…finally. Although we had a baby rainstorm earlier in the month, this weekend marked Napa’s first consistent rainfall since April. In our Mediterranean Climate, rain means fall is officially here and winter is just around the corner. Temperatures are dropping. Daylight is waning. And moisture will return to the soil again. Complete these five tasks to prepare your school garden for fall and make the most of your outdoor learning opportunities during the rainy season.
- Plant Cover Crops. Cover crops, or “green manures” are a plant-based method for replenishing soil nutrient content, maintaining soil tilth, and preventing annoying weeds. Summer crops tend to be heavy feeders–they use a lot of nitrogen to produce the juicy fruits we enjoy in late July and early August (e.g., corn, tomatoes, melons and pumpkins). Cover crops such as fava beans, field peas or hairy vetch facilitate capture and storage of nitrogen from the atmosphere to replace what was used to produce these fruits. Grasses such as oats or rye provide easy to turn in organic matter and suppress weedy pests during the wet season.
- Reset the Irrigation System. Almost all plant problems begin with too little or
too much water. To maintain plant health, adjust your watering schedule according to the changing weather. Although I had already adjusted the settings on our drip irrigation system so the raised beds were getting one watering rather than two each day, this week I turned the timer off completely in anticipation of the rain on Friday. With just under an inch of rain, I feel comfortable leaving our system off for a week. I’ll check the moisture levels next Monday, but with overcast skies and cooler temperatures, the peas, cilantro, onions, carrots, and lettuces should do just fine. Follow these instructions for an easy DIY Rain Gauge.
- Search for Pests. Wherever there is moisture, snails and slugs and weeds follow. Pull small weeds before they grow out of control and collect invertebrate pests before they reproduce. Friday afternoon, I borrowed a few third grade students to collect the snails that had come out of hiding to slide along the wet wood of the raised bed. We found over a dozen large snails and made terrarium habitats for them. Not only is this good pest management, but the snails will become an observation opportunity for students studying the unique and diverse life cycles of different organisms (NGSS 3-LS 1-1).
- Protect Harvested Seeds. I like to leave some plants in the ground long past their prime to demonstrate the life cycle of the plant and provide a simple task for
students in the garden. However, once it rains, seeds are susceptible to mold and rot. Move all collected seeds indoors, but do not leave them in the toolshed. Although it seems like the logical place to store seeds, the temperature is not ideal for long-term storage. In addition, vertebrate bests (mice, rats, etc.) will be looking for a food sources right now. Let all seeds dry out completely before storing in paper bags or envelopes. I use a wood wine box kept in a cool dry shelf in the science lab to store seeds I want to be viable in the future.
- Leave Food for the Birds. Conventional wisdom urges us to clean up the summer crops as they approach senescence, but don’t remove those sunflowers just yet! Lots of small birds feast on the nutritious seeds well into November, if you let them. Instead, leave the skeletal stalks and teach students to notice numbers and types of birds that visit them.
School gardens are a year-round responsibility. Planning for a successful spring harvest starts now. Completing these five simple but important fall tasks ensures your school garden will be well protected in the rainy season.