Spring Tree Care for Landscape Professionals

Spring is an important time to assess tree health, correct site issues, and set trees up for strong growth through the season. For professional landscapers, routine spring maintenance should focus on protecting the root system, improving soil conditions, monitoring for pests and diseases, and preventing avoidable trunk and root damage.

One of the simplest and most effective spring practices is refreshing mulch around existing trees. Mulch helps regulate soil moisture and temperature, suppresses weeds, reduces competition from turf, and gradually contributes organic matter to the soil.

Before applying new mulch, lightly rake or loosen last year's mulch if it has become compacted or matted. Then apply fresh mulch to maintain a total depth of approximately 2 to 3 inches. The mulch ring should extend as far as practical, with a minimum diameter of about 3 feet for smaller trees. Larger trees benefit from wider mulch rings that extend farther toward the drip line.

Avoid piling mulch against the trunk. “Volcano mulching” traps moisture against the bark, promotes decay, encourages girdling roots, and can lead to long-term structural failure. Keep mulch pulled back 2 to 3 inches from the trunk flare so the root collar remains visible and dry.

Organic mulches such as arborist wood chips, shredded bark, or composted wood material are preferred because they improve soil structure over time. Avoid excessive mulch depth, as thick layers can reduce oxygen movement into the soil, interfere with water penetration, and encourage roots to grow into the mulch layer rather than the surrounding soil.

Newly planted trees require careful mulch placement. Apply mulch beyond the root ball and outward into the surrounding soil area to encourage root expansion. Keep mulch away from the trunk and avoid burying the root flare.

Do not apply a heavy mulch layer directly over the root ball. Excess mulch can interfere with water movement, reduce oxygen availability, immobilize nutrients, and create conditions favorable for root problems or mulch fermentation. A thin, properly placed mulch layer around—not against—the tree provides the benefits of moisture conservation and weed suppression without compromising root health.

Spring fertilization should not be automatic. Trees growing in maintained landscapes often receive nutrients from surrounding turf or landscape beds, and unnecessary fertilization can cause excessive shoot growth, increase stress, or contribute to nutrient runoff.

Fertilize only when a soil test or clear deficiency symptoms indicate a need. If fertilization is recommended, select the appropriate nutrient formulation based on test results and apply it after leaf expansion, when the tree is actively using nutrients.

Slow-release or organic fertilizers are often good options because they provide nutrients gradually and support long-term soil health. Synthetic fertilizers can be effective but must be applied carefully to avoid over-fertilization and potential impacts on nearby waterways. Always follow label directions and local regulations.

Water management is critical in spring, particularly for newly planted or stressed trees. As trees resume active growth, consistent soil moisture supports root development and canopy expansion.

Deep, slow watering is more effective than frequent shallow watering. The goal is to moisten the root zone without saturating the soil. Overwatering can be just as damaging as drought, especially on poorly drained sites, and may contribute to root rot and other decline issues.

Watering needs vary by species, soil type, site exposure, and tree age. Newly planted trees require more frequent monitoring, while established trees generally benefit from supplemental watering during extended dry periods.

Removing grass from beneath tree canopies is a valuable practice, especially for trees in decline or trees growing in compacted, high-maintenance areas. Turf competes with tree roots for water and nutrients, particularly in the upper soil layers where many fine absorbing roots are located.

Eliminating turf under the canopy also reduces the need for mowing and string trimming near the trunk, both of which are common causes of bark injury. It can also reduce soil compaction from repeated equipment traffic and improve air and water movement into the soil.

Where appropriate, replace turf with a 2- to 3-inch layer of organic mulch. In some commercial, municipal, or high-visibility sites, complete turf removal may not be practical but expanding mulch rings where possible can still provide meaningful benefits.

Many insect pests and disease pathogens become active in spring. Regular inspections allow landscape professionals to identify issues early and intervene before damage becomes severe.

Look for signs such as abnormal leaf color, premature leaf drop, canopy thinning, dieback, trunk wounds, boring dust, scale insects, webbing, fungal fruiting bodies, or unusual swelling and cankers. Correct identification is essential before treatment.

Use an integrated pest management approach. Start with cultural and mechanical practices such as improving plant health, reducing stress, pruning out infected material when appropriate, and improving site conditions. Chemical controls should be used only when necessary, and only after proper diagnosis. Follow all pesticide labels, timing recommendations, and local regulations.

Spring is also a good time to evaluate trees for damage from winter storms, snow load, ice, and wind. Look for broken branches, cracked limbs, including bark, deadwood, hanging limbs, and trunk defects.

Minor dead or broken branches can often be pruned as part of routine maintenance. Larger structural concerns, storm-damaged trees, or trees near people, buildings, parking areas, or utilities should be evaluated by a qualified arborist. Proper pruning cuts and timing are important to avoid unnecessary stress or decay.

Effective spring tree care begins with the root zone. Proper mulching, appropriate watering, soil-based fertilization decisions, turf reduction, and early pest monitoring all contribute to healthier, more resilient trees. For professional landscapers, these practices not only improve tree performance but also reduce long-term maintenance problems and help protect valuable landscape assets.