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Using fertilizer on your lawn can lead to water quality problems in the lake. When we fertilize in spring, those nutrients can wash into the lake when we have rainstorms - even if you don't live right next to the lake. Once in the lake, those nutrients feed aquatic weeds and algae all spring and summer. There's nothing fun about lake weeds and toxic algae blooms! And then there's the time you spend buying and applying fertilizer. Wouldn't it be nice to use that time for something fun instead? Fishing? Napping? Playing with the kids?

 

TAKE THE PLEDGE TO PROTECT FUN!

 

Is this going to fix all the water quality problems in Big Lake? No. But skipping the spring fertilizer is an easy place to start.

 

 

Skip fertilizing in spring. Fall is the best time to fertilize northwest lawns, but only if they really need it. When you do fertilize, be sure to use slow-release nitrogen. (Organic fertilizers are almost always slow-release.) And choose a fertilizer with little or no phosphorus - our local soils already have plenty.

Fertilize naturally - with your lawn clippings. Grass clippings are the perfect organic, slow-release fertilizer already. Just leave them on the lawn where they'll slowly break down and feed the soil.

Get a soil test to find out if you need fertilizer. Using lawn fertilizer is a bit like taking vitamins. We're usually not sure if our bodies need vitamins, but we take them anyway because we want to be healthy. When we take more than we need, our bodies flush it out as waste. Similarly, your soil and plants may not need the nutrients in your fertilizer. When you fertilize, extra nutrients get flushed away in rain runoff and end up in the lake. A soil test will tell you what your lawn really needs, so that you're not wasting money and time. Not to mention polluting the lake!

This spring and fall, we're partnering with the WSU Shore Stewards to offer FREE soil testing to Big Lake residents. We do all the work, you get the results! Contact Cristina Ocana Gallegos at 360-395-2369 or c.ocanagallegos@wsu.edu for your free test!

Follow the directions if you choose to fertilize. Every bag of fertilizer will have instructions on the back for how to apply it at the correct application rate. (Your soil test might suggest a different application rate. If so, follow the soil test recommendations.) If your lawn is near a ditch, catch basin, or the lake, leave a 10 to 15-foot strip of unfertilized area as a buffer. And never apply fertilizer 24 hours before a rain event - otherwise it'll wash right off your lawn and into the lake!



TAKE THE PLEDGE TO PROTECT FUN!

 

So your soil test says you need fertilizer. How to pick a fun-friendly one?

The most important things to look for are a low phosphorus number - ideally zero - and a high percentage of slow-release nitrogen. The graphic below shows how to understand a fertilizer label.


N-P-K: It's always best to choose a fertilizer with lower N-P-K numbers than a higher ones. It might seem like you're getting a bigger bang for your buck with higher numbers, but you're more likely to cause pollution if you accidentally over-apply the fertilizer, or if you use a fertilizer that has nutrients that your soil doesn't need. Soils can only handle so many nutrients, and anything over what they can absorb gets washed away during the next rain. A fertilizer made of organic ingredients like feather meal or other byproducts will almost always have smaller numbers than one made of urea or other chemical ingredients.

Nitrogen: It is important to use a fertilizer with a large proportion of slow-release fertilizer. Ideally, 50% or more of the nitrogen in your fertilizer should be slow-release. Nitrogen is very soluble in water, which means it washes off very easily with rain or irrigation. Without a slow-release component, all that nitrogen will wash away in the next rainstorm before your lawn gets a chance to use it! When nitrogen gets into the lake, it feeds lake weeds. Boating and swimming in weeds is a fun-killer for sure!

Phosphorus: Soils in Skagit County usually have plenty of phosphorus in them naturally. Phosphorus is a primary driver for algae blooms in fresh water. Using low- or no-phosphorus fertilizers protects fun!

This spring and fall, we're partnering with the WSU Shore Stewards to offer FREE soil testing to Big Lake residents. We do all the work, you get the results! Contact Cristina Ocana Gallegos at 360-395-2369 or c.ocanagallegos@wsu.edu for your free test!

Soil tests run about $20, plus shipping. If the lab you use gives you a choice, be sure to choose to get results WITH recommendations so that they interpret the results for you.

How to sample: You'll find a great guide on how to take your soil sample here: https://catalog.extension.oregonstate.edu/ec628.

Where to send it: Below are several labs recommended by the Skagit Conservation District.


TAKE THE PLEDGE TO PROTECT FUN!

 

 

 

 

TAKE THE PLEDGE TO PROTECT FUN!

 

 

 

Send us a note or give us a call! Email jasonq@co.skagit.wa.us or call 360-416-1400 and ask for Jason Quigley.

Big Lake Photo Credit: Northwest Aquatic Eco-Systems. Used with permission.