Fertilizing evergreens in the winter can help to prepare them for growth in the following spring as well as provide them with enough nutrients to survive the winter and remain green. Fertilize your evergreen just as it is preparing to enter dormancy for the winter period.
A “complete” fertilizer — one that supplies the macronutrients nitrogen (N), phosphorus (P), and potassium (K) — is often recommended. A fertilizer analysis of 10-8-15 means the fertilizer has 10 percent nitrogen, 8 percent phosphorous, and 15 percent potassium.
Winter's dryness leads to leaves lacking water when the roots aren't able to take up moisture and replace what's missing. Worst case scenario, the evergreen will drop needles and branches will die. You can try to avoid winter burn by keeping the plant adequately watered as winter approaches.
Regular, repeatable foliar applications or deep-root treatments can help protect your needled evergreens from infestation. Good cultural practices like watering in drought and mulching for soil moisture retention can keep your evergreens from becoming stressed and susceptible to disease.
The best time to fertilize evergreens is said to be before new growth expands in early spring. This may start in April, depending on your region and the specific tree you're fertilizing. Be careful when fertilizing later in the summer season once the weather becomes drier.
We also recommend Greenskeeper's Secret All Purpose Fertilizer for Vegetables, flowers, fruit, nut and shade trees and hardy evergreens and shrubs. For best results, use according to the following directions and water thoroughly after each application.
Extend the beauty of your garden to the rest of your landscape with Miracle-Gro Tree and Shrub Plant Food Spikes. Use once a season, in the Spring and Fall, for lush, beautiful foliage and vibrant color on all deciduous, evergreen, and flowering trees and shrubs.
Evergreens have very strong leaves that are rolled up as long, thin needles. This special needle shape, along with a waxy coating, allows the evergreens to conserve water during summer and winter, which is needed for that continued photosynthesis process.
Epsom salt can improve the blooms of flowering and green shrubs, especially evergreens, azaleas and rhododendrons. Work in one tablespoon of Ultra Epsom Salt per nine square feet of bush into the soil, over the root zone, which allows the shrubs to absorb the nutritional benefits.
Once the needles or fronds turn brown, they stay brown. Depending on the cause of the browning, an evergreen may be able to generate new growth from the tips, but sometimes the tree ends up looking like a tree made up of bottle brushes. Many arborvitae trees succumbed to the drought of 2012.
There are so many different reasons why your tree could be turning brown: diseases, a lack of nutrition in the soil, dehydration, or an infestation. Each of those problems could lead you to another problem that you have to fix before you can save the tree. In winter, the culprit is likely to be soil that is too cold.
Common factors include drought, high winds, and extreme temperatures. One of the top concerns for evergreen browning is water loss. While coniferous trees have adapted to retain moisture and nutrients in harsh conditions, there are times when the foliage doesn't receive enough water to keep up with its needs.
For example, adding coffee grounds or organic matter around your evergreens' soil is a good place to start if you need to increase your soil's acidity. But it's not a good place to end. While your tree would get a tiny dose of nitrogen, it'd miss out on its phosphorus (P) and potassium (K) that it needs.
Fertilizing about 2-3 times a season is the norm for evergreens, however, applying nutrients later on in the season, especially after about mid-July is detrimental.
You should water your evergreen tree frequently throughout fall. Water enough to keep the soil consistently moist but not saturated, and keep watering all the way up until the ground freezes.
If you are not sure whether or not your tree has been overwatered, there are a few other signs to look for. For example, leaves that are yellow or wilted can be a sign of too much water. You should also check for any fungal growths around the base of the tree. These are often indicative of overwatering as well.
The causes behind evergreen shrubs turning brown are generally when they face soil problems and heat stress. In addition, nutrient deficiency, unavailability of water, and some environmental factors can also cause discoloration.
Too Much Sunlight
Sometimes, there will be enough sunlight that your evergreen trees will dry out more quickly as well. If you've ever suffered a mild sunburn, then you know what it'll feel like when your evergreen tree suffers from sunscald. The needles and bark are both drying out.
You may think that the name says it all, but evergreen needles don't actually stay green forever. Each species of evergreen tends to keep its needles for a defined length of time. That means it is normal even for evergreen trees to lose some needles in autumn. The needles will turn yellow or brown before falling.
Evergreens and shrubs like boxwood, rhododendron, arborvitae all need special care to prevent winter burn. Spraying these shrubs with anti-desiccants could help retain moisture throughout the winter. Anti-desiccant spray is also ideal for keeping your Christmas tree green.
Spruce and coniferous trees are susceptible to environmental, insect and disease problems that can cause the trees to discolor, lose needles and possibly die. Spruce in both urban and rural landscapes can be affected. Spruce trees can show brown needles starting from the lower limbs and progressing up the tree.
As a result, trees usually respond best to fertilizer with a 2-1-1 or a 3-1-1 ratio (nitrogen-phosphorus-potassium). Commonly available fertilizers with a 2-1-1 or similar ratio are 18-6-12, 12-6-6, 10-6-4, 10-8-6 and 10-8-4.
Standard Miracle-Gro “all purpose plant food” fertilizers are synthetic and should not be used in organic gardens.
A granular, slow-release fertilizer is the best option for fertilizing pine trees. Several formulations designed for evergreens are available. An organic granular fertilizer such as Espoma Evergreen-Tone 4-3-4 will provide a slow-release, well-balanced supply of nutrients in addition to beneficial soil microbes.