How to fertilize newly planted trees


Fertilizing Trees and Shrubs and Nutrient Deficiency Symptoms

Updated: August 10, 2022

Do newly planted trees and shrubs need fertilizer?

  • In most landscapes, healthy trees and shrubs do not require fertilizers, especially when they reach their mature size.
  • It is not recommended to fertilize at planting time. Research studies show most of a plant’s energy is directed to root growth during the establishment period. The application of nitrogen during this period seems to suppress root growth rather than enhance it.
  • Trees and shrubs absorb nutrients applied to adjacent turfgrass.
  • Fertilizer is not a remedy for landscape problems. Get your soil tested if you expect a nutrient deficiency. Most trees and shrubs prefer a soil pH (acidity level) of 5.5 - 7.0.
  • Proper watering of newly planted trees and shrubs is the most important maintenance practice for establishing plants.
  • Never fertilize a drought-stressed plant.

Fertilizer types

Fertilizers are identified by a guaranteed analysis (product label) such as 10-6-4 or 5-10-5. The three numbers represent the percentages by weight of nitrogen (N), phosphate (P2O5), and potash (K20), respectively, contained in the fertilizer.

Complete analysis granular fertilizer

A fertilizer with the three major plant nutrients, nitrogen, phosphorus, and potassium, is called a complete fertilizer. Commonly used complete fertilizers for trees and shrubs have a ratio of 3:1:1. Select an analysis that supplies the nutrients your plant needs without over-supplying unnecessary nutrients. If your soil test indicates levels of phosphorus and potassium are adequate you only need to apply nitrogen. However, it is often harder to find a nitrogen-only granular fertilizer. As an alternative, select a fertilizer with low amounts of phosphorus and potassium. Secondary nutrients like calcium, magnesium, and sulfur are sometimes included in fertilizers. Read the guaranteed analysis. 

Slow-release nitrogen 

This form of nitrogen is supplied slowly over a relatively long period of time. It is usually more expensive than the more common water-soluble (fast release) nitrogen, but less likely to contribute to nutrient pollution of our water resources. Slow-release nitrogen is available at a uniform rate over the entire season. Many tree and shrub fertilizers are a combination of slow-release and quick-release sources of nitrogen.

Organic fertilizers and compost

These can be substituted for chemical fertilizers. Using shredded leaves (run collected leaves over with a lawnmower) to mulch trees and shrubs provides a slow release of nutrients as the leaves break down and eliminate the need to purchase mulch. Compost can also be used but don’t apply more than a 1-inch layer.

When to fertilize

If you do fertilize, fertilize in the fall, between late October and early December, or in late winter or early spring, between late February and early April. Never fertilize in late summer or early fall because the available nutrients will stimulate new growth at a time when trees and shrubs are preparing for dormancy.

Fertilizer application methods and rate for broadcasting

Surface broadcasting

The easiest and most cost-effective way to fertilize large trees surrounded by mulch or bare soil is to broadcast granular fertilizer on the surface of the soil. Broadcast the fertilizer on the area under the tree, beginning near the trunk to the drip line (ends of the branches). Irrigate the area after fertilizing if rainfall is not expected. Broadcasting on turf or sloped surfaces should be avoided. Sweep off any fertilizer that lands on impervious surfaces like sidewalks or driveways, do not fertilize if a heavy rainstorm is in the forecast or the ground is frozen, and don’t fertilize within 10 to 15 feet of waterways. 

Tree dripline

Liquid deep root feeding

This is a popular application method used by the commercial tree and landscape business. The nutrients are mixed in water and injected into the soil. In general, liquid application fertilizers are more expensive than granular types for the same amount of nutrient applied.

Fertilizer spikes

Compressed fertilizer spikes are another popular method used by homeowners. These are driven into the soil with a hammer. They can only be used effectively when the soil is soft and moist. Their popularity is based on the simplicity and ease of application. Follow the instructions on the product label for the correct spacing and number of spikes to use.

Foliar application

Plants can absorb nutrients through their leaves. There are various brands of liquid fertilizers that attach to the end of a garden hose for foliar application. Although plants will absorb some nutrients through their leaves, large shade trees are not fertilized using this method. However, very small trees can benefit from this fertilizing method, if a nutrient deficiency is identified from a soil test. Applying fertilizer diluted with water to the foliage and also on the soil around the plants is done when the leaves are fully developed in late spring to early summer. It is very important to follow the directions on the product. An excessive concentration of fertilizer, especially if applied during the hottest time of the day, can burn the foliage. Foliar fertilization is a common way to apply chelated iron to plants suffering from iron chlorosis. The benefits of foliar application of nutrients are only seen for one season.

Fertilizing evergreen trees and shrubs

  • Fertilize evergreens only when it is recommended in a soil test report.
  • The feeder roots of evergreen trees and shrubs are very shallow and excessive rates of quick-release fertilizer can damage them. Broadcast a granular fertilizer uniformly on the soil under the shrub and a little beyond the drip line of the shrub (refer to the illustration above). Use a maximum application rate of 2 to 3 pounds of nitrogen per 1000 sq. ft. and follow label directions. 
  • A lower rate of nitrogen fertilizer is used around foundation plantings to reduce excessive growth and the resultant need for pruning and trimming. 
  • Many evergreens are acid-loving plants including rhododendron, azalea, camellia, mountain laurel, pieris, some hollies and pines, and leucothoe. They require a soil pH range of 4.5 to 5.5. Boxwood and yew need a pH range of 6.5 to 7.2. Fertilizers prepared for acid-loving plants include materials, such as iron sulfate, to maintain an acid soil. Repeated applications without checking the soil pH can actually make the soil too acidic. Avoid the use of aluminum sulfate unless trying to turn Hydrangea macrophylla (bigleaf hydrangea) blue.

Nutrient issues

Deficiency symptoms

Nitrogen
Nitrogen deficiency Photo: John Ruter, University of Georgia, Bugwood.org
  • Yellowing or chloritic older leaves.
Iron Chlorosis
Iron deficiency in rhododendron. Photo: George Hudler, Cornell University, Bugwood.orgIron deficiency on Northern pin oak (Quercus ellipsoidalis). Photo: Joseph O'Brien, USDA Forest Service, Bugwood.org
  • Iron chlorosis is a symptom of a soil pH problem. Iron in the soil becomes less available to plants when the soil pH is above 7. 0. Chlorosis is an interveinal yellowing of new leaves. This deficiency can be temporarily corrected by applications of chelated iron to the foliage or the soil.
  • The soil pH should be corrected or the symptoms will gradually recur. If the pH is too high (alkaline), sulfur and/or iron sulfate are applied to the soil to lower the pH.
  • Follow the directions based on the results of a soil pH analysis. If chlorosis persists, have the soil tested again. Manganese (Mn) and zinc (less common), are other nutrients that become less available in alkaline soils. It is best to test first and avoid misapplication.
  • Some other conditions that can cause chlorosis include poor soil drainage, over-watering, over-mulching, planting too deeply, root nematodes, or a root injury.
Magnesium
Magnesium deficiency on sweetshrub (Calycanthus) Photo: John Ruter, University of Georgia, Bugwood.org
  • In very sandy soils, magnesium deficiency can also be a serious problem with acid-loving plants.
  • These symptoms generally appear as chlorosis of older leaves and short, unhealthy new growth.
  • A leaf tissue test is the most accurate method to determine this deficiency and some soil testing labs perform this test. However, it is more expensive than soil testing.
  • The deficiency can easily be corrected by applying 3 tablespoons of magnesium sulfate (Epsom salt) per 100 square feet and irrigating thoroughly. Do this 2 years in a row.

Problems caused by excess fertilizing

  • Excess nitrogen fertilization can produce long succulent shoots that are attractive to various sucking insect pests, like aphids.
  • High fertilizer concentrations can cause root damage or “burn”.
  • Excessive use of fertilizer in the landscape can contribute to the nitrogen and phosphorus contamination of groundwater, streams, rivers, and ultimately the Chesapeake Bay. Nutrient runoff can easily occur on slopes. Nutrient pollution of groundwater can happen on many different soil types with any type of misuse of fertilizer but is more likely to result from fast-release fertilizers applied to sandy soils.  
  • It is very important to select the correct guaranteed analysis fertilizer, use slow-release whenever possible, and always read the label instructions.

Based on publication HG 23 Fertilizing Landscape Trees and Shrubs, Author and illustrator: Raymond Bosmans (retired), University of Maryland Extension Specialist, Home and Garden Information Center. Reviewed by Andrew G. Ristvey, UME, Senior Agent. Edited by Jon Traunfeld, HGIC Center Director, Extension Specialist, Fruits, and Vegetables.

Still have a question? Contact us at Ask Extension.

Fertilize newly planted trees?

Issue: May 12, 1997


Fertilize newly planted trees?

Question:

I live in Ruidoso. In late December 1996, I planted ten dwarf Alberta spruce; in April 1997, I planted ten green mound junipers, and then seven mugo pines. All the plants are very small, but I used no fertilizer when I planted them. They are looking good now, but I wonder when I should begin fertilizing them. Also, what type of fertilizer should I use? I have them surrounded with pine bark to prevent water loss. I want to xeriscape my new home at this 7000 ft. elevation.

Answer:

Regarding fertilization of newly planted trees -- don't! For at least the first year, their nutrient needs will be minimal. During this time they are establishing their root systems, and fertilizer (especially nitrogen which stimulates stems and leaves) will not be appropriate. You may begin a light fertilization a year from now as the leaves are forming, but for this year, be patient.

The type of fertilizer is not especially critical. You can purchase fertilizers which are specially formulated for trees, or you can use a general purpose fertilizer. Just be certain that the fertilizer is not a "weed-and-feed" product containing a postemergence herbicide which could harm the trees.

When applying the fertilizer around the tree, don't put it too close to the trunk and be certain not to put it all in one spot - it can burn the tree if too much salt is absorbed by the roots. General purpose fertilizers contain nitrogen, phosphorus, potassium, and in some cases trace nutrients. Nitrogen is needed for growth of stems and leaves. Phosphorus is needed for good plant health and energy in the plant. It stimulates flowering and fruit development, not your main purpose in growing pines, juniper, and spruce. The potassium is needed for good root development and plant health. Trace nutrients are used in very low concentrations but are sometimes a limiting factor in plant growth in New Mexico. The nutrient the trees will need most is nitrogen; however, they also need the others.

It would be wise to take a soil sample to determine what your soil needs to support good tree growth. Your local County Extension Service can advise you as to the proper method to collect the sample and tell you where you can get the soil tested. They can also help you understand the results of the soil test if you need help.

As to the xeriscape, you are off to a good start. Some people who live at lower elevations in New Mexico may question the mugo pines and dwarf Alberta spruce, but at your elevation they are appropriate if irrigated properly. The spruce will need more irrigation than the pines, but the needs of each species can be supplied with a properly designed irrigation system. The use of mulch is also a good idea, especially when starting trees as it not only reduces evaporation of water from the soil, it keeps grass from competing with the developing root system of the trees, and it keeps lawn mowers and weed whackers away from the tender bark of the young trees.


Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: [email protected] edu, office: 505-865-7340, ext. 113.

Links:

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at [email protected], or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!

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Fertilizers for trees: when, how and what to apply

You can get a high yield from fruit trees, create a unique alley of coniferous plants only with the right top dressing. In the land without fertilizers, there are not enough nutrients for full growth and fruiting. In addition, there are no trace elements that increase resistance to viral, microbial and fungal diseases. Consider which fertilizer for a tree to choose. When and how to submit it.

Fertilization targets for trees

The productivity and beauty of plants in the garden directly depends on the type of soil. Fertile soil can not be fed during the first years of the plant's life. In central Russia, in particular in the Moscow region, more than 70% of the plots have unproductive soddy-podzolic land. And it requires constant fertilization in order for the plant to develop properly, form new shoots, ovaries and fruits.

General objectives of tree fertilization:

  • Activation of plant growth, increase in the quality and quantity of fruits.
  • Improving the immunity of trees, protection from pests and diseases.
  • Nutrition of roots, trunks and foliage with essential microelements and minerals.
  • Replenishment of reserves of nutrients in the soil.
  • Reducing the acidity of the soil, if necessary.
  • Acceleration of growth of coniferous and deciduous trees.

Top dressing is carried out according to the seasons: in spring, autumn, during the growing season, less often during fruiting. In addition to fertilizing, caring for garden trees includes cleaning fallen leaves, dried branches, crown formation, sawing off diseased branches and additional protection, treatment for diseases.

Seasonality of fertilizing

Active period of adding microelements to the soil: autumn, when trees are deficient in phosphorus and potassium, and in spring, when the juice begins to flow along the trunks, branches, swelling of the buds. In the spring, they feed the earth twice: when the plant awakens and after 3 weeks.

What kind of fertilizer trees need depends on their type, soil composition and natural disasters. For fruit plants most often contribute:

  • Spring ammonium nitrate with urea.
  • At the end of flowering - complex granular fertilizers.
  • During fruiting, formulations without nitrogen to delay ripening.
  • In autumn, potassium and phosphorus.

Consider the type of plant. So, it is better for apple and pear trees to make organic matter with a minimum amount of nitrogen compounds. The best option for the second spring bait is 1.5 cups of ash infusion with 30 g of ammophoska per square meter. meter. Make the solution into the wells along with watering.

What fertilizers do apple, cherry, pear trees need

Apple and pear trees are similar in terms of growth stages, structure and fruiting time. Both trees do not like an excess of nitrogen agents. The following fertilizers will be useful for them:

  • The first spring dressing should replenish the supply of phosphorus and potassium.
  • The second, 2-3 weeks after the first, includes organics: 1.5 cups of infusion on ashes and 30 g of ammofoska. This is enough for 1 m² of area. Watered under the root.
  • At the end of spring, copper and boron are replenished. You can mix 2 g of copper sulfate with 0.5 g of boric acid per 10 liters of water. This is enough to water 1 mature tree or 2 young plants.
  • After harvesting the fruits, replenish the supply of potassium. To do this, water with a solution of potassium monophosphate in the amount of 10-15 g per 10 liters of water.
  • Once every three years, after fruiting, apply 30 g of double superphosphate per square meter around the trunk.

Trunks are whitewashed in autumn. It protects against sudden changes in temperature, infections and raids of wild animals. The same procedure should be carried out in the spring to protect against sunburn. To prepare the mixture, you can take 2.5 kg of freshly slaked lime, 300 g of copper sulfate or 500 g of iron sulfate. Pour all this into 10 liters of water and add 100 g of whitewash to them.

Caring for cherries and cherries is slightly different from apple and pear. What fertilizer does this tree need:

  • During the period of mass blooming of buds, it is worth applying compost, manure or organic purchased mixture for fruit trees.
  • In June and July they feed 2-3 more times with an interval of 3 weeks. They also add organic matter. With chicken manure, proportions must be strictly observed so as not to damage the roots.

Nitrogen fertilizers can be applied from early spring to mid-summer. Late feeding is not needed. It will delay the preparation of the tree for winter. Trace elements are introduced in the spring. Suitable urea, ammonium nitrate, potassium salt, superphosphate. The amount and frequency of top dressing depends on the age of the tree and the type of soil.

Fertilizer for coniferous plants

Perennial evergreen trees also need care. But they don't need as many nutrients as fruit plants. We need microelements for a set of cell mass and for building greenery.

Fertilizers for coniferous trees are also applied seasonally:

  • Mineral mixtures with magnesium are applied in spring. It is close in structure to chlorophyll and is needed for the photosynthesis of needles. Suitable dolomite flour in the amount of 0.5-1 kg per tree.
  • In early spring, young shoots can be fed with calcium. But a small amount. Combined fertilizers are chosen, where the composition contains a small amount of easily digestible calcium.
  • Add fertilizer with sulfur and iron. Potassium humate, combined fertilizers for coniferous plants are suitable.
  • Fertilize with potassium in the summer to prepare the plant for winter.

The best feeding option for conifers is to apply granular micronutrients to the soil around the trunk. They gradually nourish the soil and the plant.

Additional feeding

A tree can get the necessary trace elements and minerals through injections. The nutrient solution is injected directly under the bark. "Injections" are arranged so that the plant itself gradually absorbs the substances contained in the container.

Such fertilizers for fruit, coniferous trees are selected after biochemical analysis of the plant. Specialists identify which microelements are missing for proper growth and, based on the analysis, prepare a nutrient mixture.

Injectable tree fertilizer can be ordered from Mauget. Medicinal preparations for fruit, coniferous and deciduous plants are also presented there.

Fertilizer for fruit trees and shrubs in the spring at planting

Contents:

  • When to fertilize
  • Types of fertilizer
  • Basic methods of application
  • Standard fertilizer application rates
trees and shrubs are carried out in autumn or spring. The future development of plantings, their lifespan and productivity depend on how well the work on the site is carried out. In order to accelerate the survival of seedlings and stimulate fruiting in the foreseeable future, fertilization becomes an obligatory step when planting trees. This lays the foundation for future crops. We'll have to try to grow a garden.

The main tree species on the Russian plots are apple and pear trees. The classification divides other plants into the following categories:

  • medicinal - viburnum and sea buckthorn, as well as hawthorn and chokeberry, wild rose and honeysuckle;
  • shrubs - raspberries, black and red currants, shadberry and gooseberries;
  • fruit creepers such as actinidia and grapes;
  • cultivated forest berries - blueberries and lingonberries, depending on the soil - cranberries, blackberries and blueberries;
  • exotic plants - goji, gumi, medlar, dogwood and, if space permits, walnut.

Choosing suitable tree species for the site should be based on the main criteria. These are the requirements for the distance between plantings, taking into account the height (so that the high ones do not obscure the low ones), the compatibility of the trees themselves and their pollinators. Other factors to consider: planting area, maturation time, compatibility, soil requirements (some acidic, others alkaline and neutral). Also, plants differ in requirements for shade and light, watering and fertilizing seedlings of fruit trees in spring. From some crops, the harvest can be expected literally next year, from others - 7 years or more.

When to fertilize fruit trees in spring

Before planting young trees and bushes, you need to zone the garden plot and allocate space for each crop, taking into account its needs. Young growth can be planted in spring and autumn (the corresponding planting dates can be found in another article on the site). In spring, you can’t focus only on warm weather: usually at this time, purchased seedlings are already hatching and buds are blooming. Work begins as soon as the snow melts, while the seedlings are at rest. It is time to finish planting when the buds swelled on the seedlings.

Fertilizing when planting fruit trees in spring should provide enough nutrition for the seedling for 2-3 years. Caution is required with nitrogen preparations: if you apply more than necessary, the seedlings take root more slowly and may die as a result.

The feeding area for each seedling must be appropriate for the type of soil. On depleted soils, they dig a planting hole for a pear or apple tree 0.8 m deep and about 1 m in diameter. Under stone fruit and berry bushes, a smaller hole is needed (0.4 m deep and up to 0.7 m in diameter). The selected preparations are laid at the bottom in the recommended dosage, after which a little earth is poured, humus is added and seedlings are placed in the hole. It is important that the roots do not touch the chemicals, otherwise there will be a burn.

Types of fertilizers and their effect on trees in the garden

Experienced gardeners remind you that nitrogen mineral supplements are not involved in planting. Instead, they use biohumus, compost, rotted mullein or humus. Of the available mineral products, double superphosphate is more often chosen. Wood ash is added to it to enrich the soil with potassium and trace elements.

If there is no ready-made humus or compost at hand, you can buy suitable fertilizers when planting trees in the spring in the store in the form of organomineral compounds and biohumus.

Ready store mixes based on horse manure and bird droppings, humus and peat manure have a good effect on seedlings. They are packed in convenient containers and bags, enriched with all the elements necessary for plants.

Another option is to buy a universal preparation with an organomineral composition (for example, Universal or Robin Green). The peat shell of each capsule will protect the roots from burns, and the gradual release of nutrients will ensure long-term feeding of plants with biocomponents.

A proven option for spring feeding of seedlings of fruit trees — potassium and sodium humate in the form of a solution for irrigation and a tablet form. Both options suggest ease of use and effectiveness of exposure to root and foliar top dressing.

The main methods of fertilizing fruit trees

The selected option for feeding fruit tree seedlings in the spring after planting is used after mixing with fertile soil and compost. The substrate is evenly distributed along the bottom and side walls of the landing pit, 5 liters of water are poured.


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