January 23, 2016
Whether you call it global warming or climate change, we’re experiencing the build-up of excessive heat energy in the Earth’s system, according to the National Oceanic and Atmospheric Administration (NOAA). Additionally, we’re forecasted to experience the periodic increase in ocean temperatures along the equator that cyclically brings us El Niño. This large-scale interaction of warmer ocean temperature and atmospheric conditions typically brings wetter-than-average conditions over western and northern United States. The prediction regarding El Niño and the forecast of heavy rain may lead folks to believe that the drought is over. Unfortunately, this is not true.
While it’s possible that the heavy rain forecasted for this El Niño may not materialize in our area, if it does appear, it won’t reverse the water shortage for our state. Marin is lucky that we don’t have an agricultural burden on our water supply, so if the rains fill our reservoirs, we’re in pretty good shape locally. But the state water supply will still be in dire straits and we still need to be conserving vigilantly.
With these unsettled conditions, and wide swings in dry and wet periods, it’s time to inspect and prepare our gardens for extreme wind and rain.
After four years of drought, our soil is dry and susceptible to erosion, one of the most common effects of heavy rain. If you have a hillside in your yard, you’ll want to make sure you have it planted to secure the soil and prevent erosion. If you have bare patches, it’s a good idea to seed it with native grasses and cover them with mulch or plant native perennials. The roots of the natives will not only hamper erosion by holding the soil in place, but roots create tiny pathways so the water can penetrate deeply and soak the soil below the surface, reducing run-off.
For steep slopes or barren hills, you will want to apply a layer of mulch to protect the topsoil. Staking temporary fiber wattle or laying down jute erosion-control netting will help areas that are newly planted or lack plants.
Prepare for high winds. Look for dead limbs hanging overhead and secure objects that might become airborne in high winds. Plants and trees may need staking to prevent breakage, and tall container plants may need support or relocation under eaves. Container plants will need good drainage to prevent waterlogging, so check the bottom of the pot to make sure the hole is in working order and remove saucers that retain water.
Removing debris from your gutters will prevent rainwater from spilling over on walkways and patios. Attach flexible tubing to your rainspout and direct the gutter water to your garden, moving it periodically to spread the soaking around to your thirsty plants. This would be a good year to consider collecting gray water for use in your garden when the rains subside. Minimally, set out a large garbage can for rainwater harvesting. Cover the can to avoid breeding mosquitos in the spring.
While it is challenging for the NOAA scientists to predict the effects of El Niño on our coast, they are able to evaluate its recent impact in East Africa, Southern Africa and Indonesia. East Africa is experiencing heavier rainfall and flooding. South Africa had a failed monsoon and is very dry. Indonesian El Niño forest fires are raging.
Our El Niño predicted timetable shows intense West Coast rainfall from December through March. But scientists cannot predict how El Niño will manifest here reliably so far in advance. Marin gardeners would be prudent to prepare now for weather extremes and batten down the hatches.