Our experts discuss how to keep your plants growing well and your garden looking good for years to come.
An existing garden that has been maintained for more than three years requires different care than a newly planted landscape. Your lawn may need to be replanted, trees may need to be pruned, and nutrients may need to be added back to the soil. We spoke to landscape experts, who share their advice on how to care for your lawn, trees, hedges and other plants long-term, and how to edit your garden as it grows. I asked you to do it. Hint: It’s okay to transplant, prune, and replace some plants.
Mature garden compilation
All landscape experts we interviewed agreed that some editing is essential as plants grow and gardens change from year to year. The key is to strike a balance between intervention and sitting back and enjoying the natural changes.
Watch your garden transform. Finding this balance in your own garden begins with carefully observing changes in the landscape. We have to take a step back and look at what’s going on. This gardening process isn’t just about pulling weeds, it’s about creating the ideal habitat. As the owner, gardener and designer, you can always see and learn what is happening and how you want to intervene sequentially.
Landscaper suggests people who have had a garden for a few seasons consider the following: How did the plants grow? Does it feel crowded? Is there bare ground?
When a garden is young, the way the plants grow is expected to be somewhat irregular. But once your garden is mature, it’s a good idea to take a good look at it and see which plants need trimming or removal and which areas would benefit from adding plants. Some short-lived perennials, such as lavender, may need to be replaced after a few years.
Transplant or replace plants if necessary. Landscape architect advises clients to consider transplanting or replacing plants that are damaged, overcrowded or not paying for maintenance.
Make sure you’re interested in all seasons. Plants should be varied, for example, providing space for flowers, berries and winter color.
Irrigation system
No matter how advanced technology is, irrigation systems are never perfect. Check your irrigation system regularly as part of your seasonal maintenance routine. Sprinklers need to be inspected frequently because they are above ground and can easily become damaged or misdirected. If necessary, replace spray heads and remove any obstructions blocking sprinkler spray. Adjust sprinkler heads to avoid spraying water on walls, driveways or sidewalks.
Drip irrigation systems also require regular fine-tuning to ensure they are working properly. Expert recommends running the drip system long enough to display the emitter’s wetting pattern. Check for leaks or clogged outlets from the valve to the end of the irrigation line. Replace or unclog as needed. Expert recommends doing this check once a month.
Weeding
Pulling weeds is always on a gardener’s to-do list, whether the garden was recently planted or has been growing for many years. To suppress weed growth without using herbicides, it is a good idea to choose plants and plant combinations that fill in empty spaces and leave little room for weeds to enter. Cover bare soil with mulch.
Although most weeding occurs in the spring and summer, expert says fall is often a “second spring” in dry summer climate. Expert recommends that gardeners carefully weed in the fall to prevent seed heads from falling off and germinating over the winter.
If you’ve identified areas of your garden that have ongoing problems with weeds and invasive plants, you may want to consider sheet mulching, or “lasagna gardening,” which involves layering green materials such as compost, cardboard, and grass clippings. Weed seeds decompose over the winter, forming fertile topsoil. Below that, weeds are suppressed.
Soil health
Creating healthy soil is key to the long-term health of all the plants in your garden. Over time, lawns and high-traffic areas can become compacted, and flower beds can become depleted of essential nutrients for plant growth.
Poor maintenance practices. Poor maintenance practices such as excessive fertilizer use, pesticide and herbicide use, and topsoil removal using leaf blowers can also deteriorate soil and plant health. Stopping these practices can be the first step to creating healthy soil in your mature garden.
Build soil health. Although it is best to test your garden soil and correct any problems before planting, there are several ways to help improve soil health in an established garden. Every spring, before planting, I spread seven-year seasoned horse manure over the beds. Expert added that her team uses organic fertilizers and seaweed products throughout the growing season.
Soil compaction. Soil compaction is one of the most common problems expert sees in existing gardens. By dropping leaves to form a natural mulch, allowing plants to spread and cover the soil, and stopping the extrusion of topsoil, it can help compacted soil begin to heal. Your lawn can benefit from core aeration.
To help break down heavy soil, expert recommends adding calcium slowly over several years. Gypsum is a common calcium-based soil additive used for this purpose. To replenish soil nutrients, high-quality compost tea, sea kelp, and humates are important tools in our tool kit.
Lawn
Over time, lawns often become compacted and grass plants begin to show signs of stress. Peeling patches, yellowing patches, and areas with more weeds or moss than grass are all common problems in well-established lawns. Start by addressing soil health and compaction issues. If you can’t drive stakes into your lawn, it’s compacted.
Soil compaction. Expert recommends using a core aerator to solve drainage and compaction problems. She says her own team uses compost to naturally feed the lawn. Raking also helps break up moss in your lawn and lightly aerates the soil.
Fertilizer. Expert strongly advises customers not to use chemical-based fertilizers on their lawns. It will probably destroy the lawn. Instead, hire a professional or use organic fertilizer. Generally, you wouldn’t overuse organic fertilizers on your lawn, adding that humates and compost tea can be your best friend. Apply each according to the directions on the package.
Best lawn care practices. Other lawn cares best practices recommended by experts include watering less frequently and more deeply to encourage strong root growth, allowing grass to grow longer between mowing especially in the summer, and reseeding to fill in empty patches.
Tree
Because tree care varies depending on climate, location, and tree type, tree care in a mature garden is best done in collaboration with an arborist. An arborist can help you address specific concerns, advise on irrigation schedules, and help you prune your plum trees for long-term garden health.
Watering. In general, there are many best practices for keeping your trees healthy. Create good, uncompacted, nutrient-rich soil around the tree. Most trees except those that thrive in dry summer climates benefit from occasional deep watering throughout the growing season. Watering stakes can be driven into the soil and used to slowly release water to the tree roots. Move the locations from the tree trunk to the drip line and turn the hose on very low for about an hour for each location for a slow soak.
Soil compaction. Typically, tree roots are rooted to prevent soil compaction and promote airflow to the roots. This includes avoiding covering tree rings with heavy rocks or covering surrounding trees with hard terrain. Arborist also says to avoid placing mulch around tree trunks. This is because wet mulch can rot if it touches the bark.
Pruning. Arborist says mature trees benefit from careful pruning to open the tree canopy to more
light and allow air flow. He says pruning goes a long way in emphasizing the beautiful structure
of the tree or the planting layers beneath it. For major pruning tasks, it is best to hire an arborist.
Failure to prune your trees can alter your garden environment in the long term. For example, arborist explains how to plant a garden with a layer of shrubs underneath shady trees. Shrubs may receive the perfect amount of sun for the first few years of your design, but after 10 years, the trees will grow and create an environment that is too shady for the shrubs. So, you can either let your beautiful Rhododendron calendula shrub die slowly, move it to a more ideal location or prune the tree above it and enjoy for years to come.
Arborist says that in most cases, it is ideal to prune trees to shape and size while they are dormant. Most trees are so resilient that they can be pruned with minimal amounts, even in summer. If you have to do a lot of logging in the summer, help the trees by giving them a little water if the soil is dry. To fertilize your trees, arborist recommends using organic matter such as leaf compost, humates, compost tea, and kelp.
Shrubs and hedges
The long-term care your shrub requires will vary depending on the type, so it’s best to work with a local expert to address your specific concerns.
Soil compaction. To break up compacted soil around existing shrubs, use a rake or shovel to completely break up the top 3 inches of soil. This will allow water and oxygen to better reach the roots of the shrub. Then cover with mulch or compost and store away from the stems. Some shrubs, such as boxwood, have shallow roots and do not like to be disturbed. In this case, lightly loosen the soil with your fingers or a small trowel and apply mulch on top.
If you use an organic fertilizer, such as kelp meal, to feed your shrubs, spread it under a layer of mulch or compost consisting of loose soil and water.
Pruning. Landscaping experts we interviewed cited poor pruning of shrubs and hedges as one of the most common problems they see in their gardens.
In general, the best pruning methods aim to increase light and air circulation, which are important for plant health, and to control the size and shape of the plant. Landscaping experts advises that when shearing a hedge, always keep the base thicker and the top slightly narrower. She says this tapered technique allows light to reach the lower layers of the plant and helps prevent damage from snow in the winter.
If your mature hedge plants have developed dead-looking branch centers due to constant cutting, check your pruning techniques. Landscaping experts says selective “windowing” of cut shrubs selectively cutting the center of the shrub with hand pruners after mowing can help increase light and air circulation. This can help prevent dead-looking centers from forming and correct them in mature plants.
Perennial plant
Division and transplantation. Several years after planting, some perennials may benefit from dividing and transplanting. It is time to replace products that have a short lifespan or are damaged.
It depends on the type of plant and the growing conditions in your garden, but the time to divide clump-forming perennials is generally after four to five years, or when the center of the clump begins to form. Perennials can grow and divide, producing healthier plants and more diversity in your plant community.
Landscaping experts adds that while dividing is a good time to remove the roots of any weeds entangled in perennials. You can replant perennials elsewhere in your garden, give them to friends or neighbors, or donate them to a local organization.
Landscaping experts says, if you have a short-lived plant like lavender and it doesn’t do well to come out in the winter, it can take a lot of time and energy to get marginal results. While he understands why many people are hesitant to pull up a plant when it fails, he urges his clients to take a pragmatic approach: Replace that plant and enjoy the growing space.
The same goes for plants that can aggressively take over your garden by spreading clumps or self- sowing. Herbaceous plants can set seeds around them, and certain plants can dominate others. We sometimes have to intervene to maintain the planned diversity in the garden.
Native and drought-tolerant plants
Native and drought-tolerant plants will need more supplemental water when they become established in the garden, but over-irrigating them can harm them later. After the second or third summer, most of the native plants or other low-water plants will be fully established, depending on the amount of rain we receive during the wet season, of the California plants he works with. It is completely drought tolerant and no longer needs additional irrigation except during dry winters.
She has found that most plants, including succulents, look lusher in the garden with a little irrigation. You can occasionally spray your plants with water to wash the dust off the leaves.
