How to Grow Conifers

Conifers are a low-maintenance addition to landscapes and container gardens. Before you purchase conifers for your lawn or landscape, examine the surrounding area for conifers that are already thriving in your climate and soil.

Research unique and rare cultivars of the common species in your area. Certified rare conifer nurseries provide hundreds of cultivars and varieties with variegated foliage, unique branching habits, and distinct cone colors.

Site Requirements

Most conifers prefer full sun and rich, acidic, well-drained soil. However, many species that can tolerate poor soils, high pH, salt, drought, and wind. The only condition conifers cannot tolerate is wet, soggy soil (except for the bald cypress).

Planting

Plant conifers the same way you plant other landscape plants. Dig a hole twice the size of the root ball, and gently pull the plant out of the container. If the plant is balled & burlapped, cut away the wire at the top and pull back the top of the fabric (to remove or not remove the burlap? We answer that question on our planting page). Fill in the hole and gently tamp down the soil.

For best results, plant the conifers in early spring or in the last few weeks of fall.

Pruning

Pruning can be as relaxed or involved as you want. Most conifers perform just fine with no pruning, except to remove dead or diseased wood.

The most common and helpful type of pruning is candling, or removing the first few inches of new growth in the spring. This will encourage dense foliage and keep the mature size in check.

Some conifers, like yews and junipers, respond well to shaping. These plants can be pruned into globes, spirals, or formal hedges, but before you pull out your hedge trimmers, read our pruning page for the best way to create artistic conifer shapes.

Conifers add seasonal interest and a unique structural element to landscapes, container gardens, and even specialty plantings like fairy gardens and railroad displays.

Browse our pages on unique cultivars to add specimen plants to your landscape, and visit our planting, pruning, and site requirement pages to learn more about how to care for conifers.

What Kind of Soil is Best for Dwarf Conifers?

Conifers are the Goldilocks of the landscape. Of all the different types of soil, conifers prefer the middle ground.

So, what does that look like?

Dwarf conifers thrive in well-drained, crumbly, slightly-acidic, loamy soils. If they are planted outside their comfort zone, they tolerate sandy soils that are high in organic matter over thick, compacted clay.

If you are planting dwarf conifers in your landscape, do a soil test to determine the pH and nutrient content of your native soil. Then, compare that to the ideal soil for conifers. In most cases, compost will improve any limiting factors in your landscape bed.

If you are planting dwarf conifers in a container, buy or make a soil mix that has the same qualities as loam, but with increased drainage. Don’t worry- we’re going to give you a few recipes for creating the perfect container mix.

Of course, some conifers may have different soil requirements. Purchase your dwarf conifers from a specialty grower who can provide specific information about the variety you want to plant.

The Ideal Soil for Dwarf Conifers

Conifers prefer a slightly-acidic version of the perfect soil: dark, crumbly, well-drained loam.

Why?

This has less to do with the fertility of loamy soils and more to do with how they hold and drain water.

Dark, loamy soils are generally fertile, but conifers are not heavy feeders. Conifers don’t have to replace leaves each spring like deciduous trees, and they tend to grow slowly, which limits how much nutrition they pull from the soil. In fact, they prefer a pH of about 5.5, which naturally limits the availability of macronutrients (nitrogen, phosphorus, potassium, sulphur, calcium, and magnesium).

However, the same properties that increase fertility- namely, organic matter and biological activity- also promote water and air movement through the soil.

Organic matter, which is decomposed plant material, creates a spongy soil structure with a variety of pore sizes. Small pores hold water, while large pores promote drainage. An even mixture of small and large pore spaces creates an ideal porosity, which is what determines how well a soil holds and drains water.

Soils high in organic matter will be dark and crumbly, so when plant guides say a plant thrives in dark, crumbly soil, they really mean the plant thrives in soils high in organic matter.

Particle size also affects porosity. Small clay particles create small pore spaces, and large sand particles create large pore spaces. Silt is a medium-sized particle that acts as a buffer between clay and sand.

Loam is the term used for a mixture of clay, silt, and sand. A loamy soil will have good porosity, and a loamy soil with organic matter will have even better porosity.

Loamy soils will absorb water easily, and retain moisture without becoming waterlogged. These soils are referred to as well-drained soils, because they drain easily without becoming too dry too quickly.

Why do plants need well-drained soils?

Because well-drained soils breathe. Soil is an ecosystem that supports insects, bacteria, plants, and other living organisms. Roots use water to pull up nutrients, but if they are constantly saturated, anaerobic bacteria begin to eat away at the roots, causing root rot.

So, when we say conifers prefer acidic, well-drained, dark, crumbly, loamy soil, what do we really mean?

Conifers are not heavy feeders, but they need a soil high in organic matter with a balanced amount of clay, silt, and sand particles so roots are able to absorb plenty of water without rotting from a lack of oxygen.

Of course, there’s always going to be an exception.

How to Identify Soil Quality via Site Assessments

Soil tests give a detailed report about nutrients, organic matter, pH, and overall soil quality. They can help diagnose deficiencies, toxicities, and imbalances.

Although annual soil tests are the most accurate way to determine exact soil properties, there’s a much more practical way to identify potential problems in your soil and also identify which conifers will thrive in your area: observe the established landscapes in your neighborhood.

There are 3 steps in a soil site assessment:

  1. Identify thriving/suffering plants
  2. Identify indicator plants
  3. Identify common signs of soil deficiencies/toxicities

A site assessment is as simple as a stroll through the neighborhood. Study other landscapes and established trees and shrubs. Use the following information to make decisions about what plants to use in your landscape, or diagnose current problems in your established plants.

1. Identify Thriving/Suffering Plants

Take pictures or notes of which plants are full and healthy. Look for:

Take special note of conifers that are common and healthy in the surrounding area.

This information can tell you what types of plants thrive in your local soil, and which specific conifers should do well in your landscape.

If you notice landscapes with a lot of variety, the soil has a healthy structure and should support a variety of conifers.

If you notice landscapes with multiples of the same few varieties, the soil may have an underlying deficiency, pH imbalance, or poor structure. (That, or your neighbors are terrible landscape designers)

Use this information in conjunction with identifying plants that are suffering or stunted to find potential problems in the soil.

Look for:

This information can tell you if there are underlying nutrient deficiencies or toxicities, and it can tell you if there are regional pests and diseases that affect certain types of plants.

The most common sign of nutrient deficiencies is chlorosis, which is an overall yellowing of the needles. This is most common with nitrogen deficiencies, but it can change depending on the pH of the soil.

Conifers aren’t heavy feeders, and they prefer a pH of 5.5, which is lower than most landscape plants. In acidic soils, macronutrients are restricted, so standard landscape plants may show signs of nitrogen and potassium deficiencies even if the soil is perfect for conifers.

Common causes of chlorosis in acidic soils are:

Common causes of chlorosis in alkaline soils are:

Find indicator plants in the area to help determine if there truly is a lack of macronutrients, or if the pH is too low for standard landscape plants to thrive.

Take special note of conifers with pest and disease problems.

Common problems may include:

Although this generally doesn’t reflect a soil issue, you should avoid planting specific conifers if established plants in the area are suffering.

2. Identifying Indicator Plants

Indicator plants give specific insight into pest life cycles, temperature changes, common diseases, and soil conditions. These plants have exaggerated or obvious signs that tell gardeners when to spray, when to plant, and when to water.

Conifers like acidic soils, so you should look for plants that thrive in acidic soils or have a specific color in acidic soils:

There are also plants that indicate alkaline, or “sweet” soils:

Although most conifers prefer acidic soils, there are conifers that can tolerate more alkaline conditions, like arborvitae and false cypress. If you have alkaline soil, ask a specialty grower (link to Conifer Kingdom) if they can recommend specific varieties for your landscape.

3. Identify Signs of Common Soil Deficiencies/Toxicities

When you are doing a site assessment for dwarf conifers, focus on symptoms of nutrient deficiencies in other conifers. This will give you the most accurate idea of how well your conifers will perform in your landscape.

Look for the following symptoms of nutrient imbalances:

These symptoms may not be a direct result of a deficiency; they might also indicate extremely low or high pH, or a chain reaction resulting from other nutrient deficiencies/toxicities.

If you notice consistent signs of nutrient imbalances, do a soil test before you plant to pinpoint the underlying problem. If the soil is truly deficient, annual compost amendments and mulch, along with a slow-release fertilizer, should be sufficient to sustain healthy conifer growth.

Amending Native Soils – How to Create the Ideal Soil for Dwarf Conifers

Conifers place a tall order, but if your soil isn’t perfectly-suited to their needs (and most soils aren’t), you can implement a few annual maintenance tasks to create a healthier soil environment.

Focus on improving porosity. There are 3 things that can prevent adequate porosity in a soil:

Although disproportionate amounts of clay and sand may cause the majority of soil issues, adding clay or sand to soil is never the answer.

Clay + sand = concrete.

Stick to increasing the organic matter and creating an irrigation schedule (link to How to Water…page) that promotes a dense, fibrous root system.

Add Compost

Whether your soil is too sandy or has too much clay, compost is the answer.

Conifers aren’t heavy feeders, so don’t use potent, nutrient-dense compost products like chicken manure or worm castings. Save those for the vegetable garden.

Instead, use all-purpose compost that can increase the amount of bulky organic matter in the soil.

There are 2 ways you can incorporate compost into the soil:

  1. When you plant your conifer, mix compost into the soil when you fill in around the root ball.
  2. Each spring, add a thin layer (1/2”) of compost over the entire landscape bed.

As you continue to add compost each year, the soil structure will gradually become more loamy.

Use Mulch

Mulch adds organic matter and conserves moisture.

A 3” – 4” layer of mulch will insulate the soil from heat and wind, which prevents evaporation. However, mulch still allows soil to breathe, which prevents root rot.

As mulch breaks down, it will add small amounts of organic matter into the topsoil. This will provide the same benefit as compost, and over time, both compost and mulch will improve porosity.

Use more acidic mulches to help maintain a low pH:

Pine needles

Pine bark

Oak leaves

However, if you don’t have access to these mulch products, you can use wood chips, leaf litter, and even grass clippings.

Recipe for Container Mix for Dwarf Conifers

Most dwarf conifers are excellent container plants (link to future guide for conifer selection), which is part of what makes them such a versatile landscape plant.

Standard potting soil is adequate for dwarf conifers, but it is not ideal.

Here are two recipes for a homemade container mix for dwarf conifers:

Simple Conifer Container Mix

This is an easy mix you can customize to fit your climate, container, or plant. Increase the amount of sand if you live in a wet climate, increase the amount of compost if you live in a dry climate, and add extra perlite or vermiculite if your container doesn’t drain well.

Recipe:

Mix ingredients well or else the sand will fall to the bottom. For extremely large containers, mix smaller batches of soil and add them in layers to ensure the ingredients are thoroughly combined.

Bark-Based Conifer Potting Mix

This mix holds more water than the simple container mix, but it doesn’t use potting soil, so it doesn’t settle as easily.

Adjust the proportions of sand or soil to improve drainage or water retention. Do not adjust the amount of pine bark, or else you may cause nitrogen burn.

Recipe:

This mixture can be difficult to combine, so you may have to make small batches and fill the container in layers.

Although conifers can be picky about soil structure, they’re usually pretty happy once they have an established root system.

Combine annual mulch and compost applications with a customized irrigation schedule (link to other page) to create a healthy, thriving soil environment for your dwarf conifers.

There are many conifers that are perfectly happy growing in less-than-ideal conditions:

Conifers that tolerate poor drainage/clay soils:

If you have clay soil, do not plant firs, yews, or 5-needle pines.

The main risk with clay soils is poor drainage, although some conifers can tolerate wet, shaded areas. Clay can become compacted and is more prone to toxicities than other soil structures. The upside to clay soil is that it is usually acidic, so if the soil is improved over time, the plant should thrive under most circumstances.

Japanese maple , downy Japanese maple , and Sweetgum are good complementary trees for clay soils.

Conifers that tolerate sandy soils:

Use compost and mulch in loose, sandy soils to gradually build up a more substantial foundation.

Most conifers will tolerate sandy soils because they drain well. If you live in a dry climate and you have sandy soil, look for conifers that are drought tolerant. Needle structure is key to identifying drought-tolerant conifers: look for 2-needle and 3-needle pines, scaled juniper needles, and blue waxy needles (like the Colorado blue spruce).

Conifers that tolerate alkaline soils:

Although these conifers may tolerate alkaline soils, you should still use an acidifying mulch, like pine bark, to help lower pH near the root zone.

As pH values rise, manganese and iron become less available to conifer roots. These plants are sensitive to mineral deficiencies, so many conifers will become chlorotic in alkaline soils. Conifers that tolerate high pH, or sweet soils, are able to handle iron and manganese deficiencies.

Conifers that tolerate coastal conditions and salty soils:

This is common near roadways and near the coast.

Ginkgo is another salt-tolerant tree that complements conifers.

Conifers can be exposed to salts either by salt spray from road treatments. Salt can either be splashed directly onto the foliage, or it can settle into the soil and cause similar symptoms to fertilizer burn.

The most common conifers to use in high-salt areas are deciduous conifers. Plants that lose their foliage in the fall are not exposed to as much salt spray as evergreen conifers. Hard pines, junipers, and other tough conifers are more salt tolerant than softer, more sensitive plants.

Conifers that tolerate windy, exposed sites:

Windy, exposed sites are prone to drought and desiccation (dehydrated needles). So, rugged, drought-tolerant trees can not only tolerate these conditions, but also provide a windbreak for more sensitive plants in the landscape.

However, don’t assume drought-tolerant means these plants don’t need irrigation. Encourage a deep, dense root system by watering new plants consistently and thoroughly (link to irrigation page). Pay close attention to plants in these locations and give them extra water during the first few years to get them off on the right foot.