Question of the Week – Number One: April 5, 2018
“Neil, what is the best time to fertilize my various plants?”
There are so many variables. You’ll have to consider things like soil types (sands require more frequent feedings than clays), types of plants you’re growing, types of fertilizer you might be using (especially organic vs. inorganic), etc. However, I’ll try to give some general guidelines.
• Fertilize in anticipation of new growth. In most cases that would mean 2-3 weeks prior to that new growth’s beginning.
Comments about organic fertilizers…
• Organic fertilizers are much lower analysis and much more slowly available for uptake by plants’ roots, so you will apply them less often. But you have to be patient – it will take a while to see the results.
Timings for inorganic plant foods…
Here are some general guidelines that may be of help. These are for high-nitrogen or high-quality all-nitrogen fertilizers (half or more of the nitrogen in slow-release form).
• St. Augustine lawns: Early to mid-April; early to mid-June; early September. (None applied in mid-summer due to propensity for gray leaf spot disease if N is applied in hot weather.
• Common bermuda: Early April; early June; early August; early October.
• Hybrid dwarf bermudas: Early April; repeat on 6-week intervals until mid-fall.
• Zoysias: Early April; early June; early September.
• Buffalograss: Mid-May.
• Fescue: Early November; mid-February; mid-April.
• Trees: Same schedule as turfgrass. In fact, they will compete with the turf for nutrients so no need to make special effort to feed them. Perhaps make one extra pass around the drip line with the rotary spreader, but be certain you’re not using a weed-and-feed product.
• Shrubs, vines and groundcovers: Every two months beginning early April.
• Annual flowers: Two weeks after planting (half-rate application); monthly thereafter. Water by hand to wash granules off leaves and away from stems.
• Perennials: Monthly during periods of active growth and leading up to bloom. Many types will go dormant part of the year. Do your best not to apply fertilizer directly to them at those times.
• Fruit trees: As new growth begins in the spring and again in early fall.
• Vegetables: Two weeks after planting; Repeat every 2-3 weeks until harvest to keep vegetables growing actively. Side-band the granules along the rows of vegetables and water by hand to wash granules off the leaves.
• Container plants: You may prefer to apply a diluted solution of a water-soluble plant food to these each time that you water them. That will give them sustained growth.