Answer #2 ·
Gardenality.com's Answer · Hi Tim - If your plants are doing fine without fertilizer then I'd say you don't have to fertilize them. Some plants do fine feeding just off decomposed organic matter, compost or readily available nutrients that exist in the soil. When the foliage of a plant starts to look a little dingy or its growth rate has slowed considerably, and I've determined it's not from insects, disease or soil pH, I feed them with an organic plant food. I never use synthetic fertilizers, and especially don't like any of the Scotts products, such as Miracle Gro. Instead, I use one called Nitroganic, but this product isn't available oustide the Southeast US. Milorganite is a comparable fertilizer and there are scads of others on the market. Reason I like these two products is that they contain 4% naturally occurring iron and also help to repel deer, of which there are many around my property. They also contain lots of natural nutrients and elements not listed on the bag and are totally non-burning, which means they're "goof proof"....and won't burn your plants. Here's a link to a page about Nitroganic and/or Milorganite...
http://www.gardenality.com/Articles/1118/How-To-Info/Fertilizing/Review-of-Nitroganic-Fertilizer/default.htmlRegarding the spirea, the bleached foliage could be due to a lack of sunlight, or possibly poor soil drainage and soggy soil? Typically, spirea prefer full to mostly sun. I have probably 5 varieties growing in my landscape including Gold Mound, Reeves, Pleno, Anthony Waterer and Little Princess and the ones in full sun are doing fine. A few Gold Mound are under some crape myrtle trees in the front and in the shade their leaves are a bleached out, light lime green color rather than golden-yellow.
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