San Joaquin UC Master Gardeners Smart Gardening Conference September 29, 2012
A fertilizer is any material containing at least one of the essential elements for plant growth that is added to the soil for the purpose of supplementing the plant nutrient supply.
Sixteen elements are required for plant growth. Carbon, hydrogen and oxygen Macronutrients: nitrogen, phosphorus, potassium, calcium, sulfur, magnesium Micronutrients: manganese, zinc, boron, copper, iron, molybdenum, and chlorine
Nitrogen: Encourages healthy vegetative, green growth Phosphorous: Phosphorous contributes to many fundamental plant processes such as strong roots and setting flower buds Potassium: Potassium (aka Potash) contributes to the overall health and vigor of plants. Helps the plant through stressed times such as disease/insect damage, drought and cold temperatures
Numbers represent the percentage of nutrient compared to filler ingredients. A 10-10-10 fertilizer contains 10% of each nutrient. A 10 pound bag of fertilizer labeled 5-10-5, would contain 5% nitrogen, 10% phosphorus and 5% potassium. The remaining 80% could be comprised of other nutrients and filler.
50-lb bag of 10-10-10 fertilizer Multiply 50 by 0.10. Do the same for calculating the amounts of phosphate and potash. A 50-lb bag of 10-10-10 contains a total of 15 lbs of nutrients: 5 lbs nitrogen, 5 lbs phosphate and 5 lbs potash. The remaining weight is filler, usually sand or granular limestone. Another example:
Multiply 50 by.08, which equals 4. To calculate the pounds of phosphate: There is no phosphate in this bag of fertilizer. To calculate the pounds of potash: Multiply 50 by.24, which equals 12. A 50 pound bag of 8-0-24 fertilizer contains a total of 16 lbs of nutrients: 4 lbs nitrogen, 0 lbs phosphate, and 12 lbs potash. This would leave us with 34 lbs of filler.
Fertilizer Lingo
Complete Fertilizers: Fertilizers that contain all three major nutrients are considered complete fertilizers. (10-10-10) Incomplete Fertilizer: Lack one or more major nutrients such as a fertilizer labeled 0-20-20
Contain either equal amounts of each major nutrient (N-P-K ratio 12-12-12) or a slightly higher percentage of nitrogen than of phosphorus and potassium (such as a 12-8-6 product). Are intended to meet most plants' general requirements throughout the growing season.
Are formulated for specific needs. They're aimed at the gardener who wants a particular combination of nitrogen, phosphorus, and potassium for certain plants or garden situations.
These feature the N- P-K ratios determined to elicit the best performance from the particular plant, as well as other elements proven valuable to that plant. Examples would be citrus trees and acidloving plants such as camellia and rhododendron.
These products are derived from the chemical sources listed on the product label. Faster acting than organic kinds and provide nutrients to plants quickly, making them a good choice for aiding plants in severe distress from nutrient deficiencies. Typically cheaper than organic
Derived from the remains of living organisms; blood meal, bone meal, cottonseed meal, and fish emulsion are just a few of the many available types. Organic fertilizers release their nutrients slowly: rather than dissolving in water, they're broken down by bacteria in the soil, providing nutrients as they decompose.
Since plants can take up nutrients continuously, it may be beneficial to provide them with a somewhat steady supply throughout their most active periods of growth. Slow-release fertilizers contain one or more essential nutrients. These elements are released or made available for plant use over an extended time period.
Liquid fertilizers are water-soluble powders or liquid concentrates that mix with water to make a fertilizer solution. The liquid nutrients generally last 1 to 2 weeks, so you need to reapply often. They are quickly absorbed, so plants get their benefits soon after you apply them. They are great as a starter solution and for a quick boost during the growing season. When properly diluted you also negate the chances of fertilizer burn. Properly diluted liquid fertilizer is ideal for use of soft, sensitive and young plants.
Granular fertilizers are meant to be worked into the soil or sprinkled around plants. They last 1 to 9 months, depending on the type After application these types of fertilizer should be watered in immediately to avoid the plants burning
Manures can be used to increase soil fertility. When manure is spread in the spring, even if aged, it is safest to wait for at least one month before planting crops. When composted manure is spread directly over the soil, it is helpful to add about 40 lbs. per 100 square feet, turned into the top 6 to 9 inches. Fresh manure also can damage plant tissue and kill seedlings. It is too hot make sure you use manure that has been processed or composted.
It is not recommended that homeowners use any manure from dogs, cats, or other meateating animals, since there is risk of parasites or disease organisms that can be transmitted to humans.
Compost feeds the soil and fertilizer feeds the plants. Compost and organic fertilizers can work together. The organic matter in compost sponges up the fertilizer nutrients until they are needed by plants. Compost also provides many nutrients that plants need in small amounts, such as boron.
Primarily need nitrogen but many crops also benefit from some complete fertilizer (5-10-5, 5-10-10, 8-16-16, and 12-12-12). Apply these fertilizers at rates of 1-2 pounds per 100 feet of row. Consider light but frequent applications of nitrogen fertilizer every 3 to 4 weeks. Avoid letting the fertilizer come into contact with the plant stems to avoid burning. Not using compost or manure? Apply fertilizer that contains both nitrogen and phosphorus before planting.
Young fruit and nut trees in the pre-bearing years (the first 2-3 years) can use more nitrogen per canopy area than mature, fully-bearing trees Wait until early summer when there is 6 to 8 inches of new growth. Apply about 2 oz of a nitrogen fertilizer, such as ammonium sulfate (21-0-0), or 16-16-16 or 1 oz of urea (46-0-0) or 2 pounds of compost once a month until leaf fall. Scatter the fertilizer on the soil under the tree, keeping it at least one foot from the trunk and water it in
Different varieties have different needs Fully-bearing, average-sized mature trees in the home orchard should be fertilized at the rates stated in Calendar of Backyard Gardening Operations for Selected Temperate Fruit and Nut Trees. (This handout can be found at the fruit tree display)
Use a fertilizer labeled for citrus Most mature citrus require regular fertilization with nitrogen. Nitrogen should be applied in January or February just prior to bloom. The second application then can be applied in May and perhaps a third in June. Avoid late-season fertilization as it may affect fruit quality, delay fruit coloring, and make the rind rough. Water the tree the day before, broadcast the fertilizer over the root zone and water in well. Withhold fertilizer from fall through midwinter.
Acid-loving plants thrive in a ph range of 4.5 to 6.5. Azaleas, Rhododendrons, Gardenias A complete fertilizer designed for acid-loving plants Fertilize during the growing season, not the dormant
Add the following to the soil: For hydrangea blooms to be blue- lower ph A fertilizer low in phosphorus and high in potassium is helpful in producing a good blue color-25/5/30 A solution of 1 Tbsp aluminum sulfate per gallon of water be applied to plants (which are at least 2-3 years old) throughout the growing season For hydrangea blooms to be pink raise ph Add dolomitic lime several times a year Use a fertilizer with high levels of phosphorus.
Do not fertilize at planting time. Four weeks after planting, use a 10-10-10 fertilizer that contains ammonium sulfate or a potassium sulfate. Sprinkle 1 ½ tbsp within 12-18 inches of each plant, but not directly on the crown or stems. Or use organic-based fertilizers such as blood, feather, or fish meal at the rate of 1 pound per plant.
For flowering annuals, use an all-purpose plant food, such as a 5-10-5 or 10-10-10 formula. Flowering plants have a special need of phosphorous and potassium to reach their blooming potential. Phosphorus will encourage big healthy blooms Foliage plants will flourish with a formula higher in nitrogen
Trees, shrubs, & vine apply 0.2 lb N in a 3 ft x 3 ft area around base of plant immediately after planting, again 6 8 weeks after planting, and the following spring Fertilizer should be applied at the drip line of trees and shrubs and not directly on the trunk or crowns. Newly planted groundcover: 1 2 lb N per 1,000 sq ft immediately after planting and again 6 8 weeks after planting
Usually when fertilizer is needed, only nitrogen is necessary. Apply fertilizer to the soil surface for these plants. Broadcast about 1 to 3 pounds of actual nitrogen per 1,000 square feet of planted area for shrubs or per 6 inches of trunk diameter for trees. With few exceptions, trees do not respond to supplemental fertilization in California. In fact, fertilizing healthy woody plants can be harmful by encouraging excessively vigorous growth.
Nitrogen and iron are the only nutrients in which woody plants are commonly deficient Fertilize only as needed and only if other problems have been eliminated as the cause of poor growth. Avoid overfertilization, especially with high nitrogen fertilizers. Overfertilization promotes excessive foliage that may increase populations of pests such as mites, aphids, and psyllids. Excessive growth may cause bark to crack, allowing entry of fungi. Excessive fertilizer may also kill roots and burn or kill foliage.
Roses in general are heavy feeders. Roses love being fed, and will reward you with more blooms if they are fertilized Stop fertilizing about 6 weeks before the first frost date
How often to apply is a subjective decision, based on the amount of time and devotion you have. What type of rose grower are you?
You like to look at roses from your window, but don't know the varietal names and only cut a few for the house. Use a granular food with of about 10-10-10, applied every four weeks according to directions. Fish emulsion applied as a liquid fertilizer when buds are about pea-size (about three weeks before each bloom cycle) will enhance bloom color. Add chelated iron for rich green foliage. During June, July and August, reduce the amount of fertilizer applied by half during but stay on the same 4-week frequency.
Realizing roses require a steady source of food, and having the time to supply it, you are willing to adopt a bi-weekly fertilizer program for the big blooms. Start with an application of granular food as first growth appears in Spring. Then begin a program of liquid fertilizers every 2 weeks Add Epsom Salts at 1/4 C per bush, either dissolved in the liquid feeding or sprinkled straight from the package onto the soil
Your "main line" is your hose, and you have had it surgically attached to your hand, since you fertilize weekly. Your main goal is a trophy in a local, district or national rose show. Use the previous mentioned rotation of fertilizers on a weekly basis, but reduce the concentration to about half of that called for on the label.
The majority of house plant fertilizers are about 20-20-20 Frequency of fertilizer application varies somewhat with the vigor and age of each plant. Houseplants should only be fertilized during periods of active growth. Plants in low light will not need as much fertilizer. Brighter light will need more
A general guideline to use is to fertilize monthly in the spring and summer and only two or three times in the fall and winter. Never fertilize when the soil is dry. Pots should be leached every 4 to 6 months. Leaching is accomplished by pouring an amount of water equal to twice the volume of the pot on the soil and letting it drain completely. This will flush out salts left behind by fertilizers
So many plants to fertilize so little time to cover them all! We re here to teach you where to find the answers!
Start by clicking here
Click on fruit trees and you will get this list You will see the following list
Along with other helpful information for growing avocados including planting, harvesting and pests you will get specifics on fertilizing
Why there is no magic number for turf There are so many different types of turf grown in our county (Cool Season vs. Warm Season grass) Size of lawn Temperature Soil types Recommend using IPM site Identify turfgrass species if you don t know what you have Will calculate how much to apply by entering species and area of lawn
Map of entire state
Red Fescue Don t Know?? That s ok! Use the turf key
Nitrogen is the only nutrient that turf grass needs on a regular basis. In general, lawns should be fertilized about 4 times a year with 1 lb. of nitrogen at each application Both cool-season and warm-season grasses require 4-6 lbs. of actual nitrogen per year. This amount is usually divided into 4 applications of 0.5 to 1 lb. of actual nitrogen per 1000 sq. ft. per application.
Grasscycling supplies about 20% of the fertilizer requirements of most grasses. Leaving your clippings on the grass after mowing is beneficial as it returns nutrients back to the soil. It is only beneficial if you follow proper watering, mowing, and fertilizing guidelines. Not this
Nitrogen: Older leaves, needles are yellowish; new growth sparse, undersized; plants grow slowly and may drop foliage prematurely. Iron: New foliage small and yellowish, except green along veins; dead spots may develop between veins; leaves drop and dry prematurely. Zinc: Leaves yellowish; new growth may be delayed; new leaves may be small, narrow; foliage may be purplish. Phosphorus: Foliage dark green, bluish, or may develop spots; shoots short and spindly; slow growth. Potassium: Foliage growth is sparse; older foliage is yellowish and may have brown tips and margins near leaf edge or between veins.
Follow the directions on the package for how much to use and how often to apply it. Overfertilizing is worse for plants than feeding them too little. Too much fertilizer causes rapid, weak growth that is susceptible to damage by pests and diseases, and excess fertilizer runs off and may find its way into the water table, causing pollution. More is not better!
Questions?
Citrus http://homeorchard.ucdavis.edu/files/140618.pdf Fruit trees: http://homeorchard.ucdavis.edu/calendar.pdf http://hoorchard.ucdavis.edu/fertilizing2.pdf blue berries: http://ucanr.org/sites/gardenweb/berries/?uid=25&ds=466 landscape trees: http://anrcatalog.ucdavis.edu/pdf/8045.pdf Lawns http://www.ipm.ucdavis.edu/tools/turf/maintain/fertwhen.html http://www.ipm.ucdavis.edu/qt/lawnfertilizingcard.html http://www.ipm.ucdavis.edu/tools/turf/maintain/ferthow.html sunset crash course: http://www.sunset.com/garden/garden-basics/crash-course-fertilizers- 00400000015144/ woody plants" http://www.ipm.ucdavis.edu/pmg/garden/environ/fertilwood.html Reading bag: http://www.calfertilizer.org/fertilizer%20facts.pdf woody plants: http://ucanr.org/sites/urbanhort/files/80113.pdf types of fertilizer: http://flowers.about.com/od/flower-gardening/a/choose-the-right-flower- Fertilizer-Type.htm reading bag: http://gardening.about.com/od/gardenprimer/ht/fertilizerlabel.htm Houseplants: http://www.ces.ncsu.edu/depts/hort/consumer/quickref/houseplants/fertilizing.html roses: http://www.ipm.ucdavis.edu/pmg/pestnotes/pn7465.html#cultural