Many may see mulching as nothing more than a cosmetic addition to the landscape but there are actually 5 crucial reasons you should mulch.
- A fresh layer of mulch really leaves a beautiful and uniform finish to plantings and the landscape
- Weed Supression
- A 3″ layer of mulch can really help in supressing broadleaf & grassy weeds by reducing the mulched surface’s exposure to the sun
- Moisture Retention
- A 3″ layer of mulch helps keep moisture levels maintained in the soil. This not only reduces the frequency of watering (saving time and money) but also keeps plants in a more active growth state while helping them perform better.
- Temperature Regulation
- For many plants that are sensitive to the ever changing early warm & cold spells of earliest Spring, mulching maintains the proper timing of their spring arrival minimizing harsh damage from late frost. It’s like a jacket for your plants!
- Erosion Control
- Whether temporary until a groundcover plant grows to provides full coverage, or whether used in areas of the landscape where erosion can potentially cause problems in soil movement due to heavy rains and wash outs – mulch can help keep the soil from washing out in those areas.
DEPTH & INTERVALS
Depth and mulching interval do somewhat work hand in hand, but there’s one thing to remember about mulching. Don’t try to eliminate intervals by doubling up the depth of application. Applying too deep of a mulch layer is more likely to cause problems than it will have benefits. Mulch accumulation can be a real problem and can cause problems within many trees, shrubs, and perennials, Root systems become shallower and more sensitive to varying seasonal temperatures such as heat and cold.
The recommended application of mulching is an initial 3-4″ layer at new landscape bed installation or for individually mulched trees, shrubs, & perennials. Follow up top dress mulch applications should be done by applying a 1.5″ – 2″ deep layer and no more – typically, a fresh top dress should be applied annually. Many people mulch in the Spring but the timing is more of a customer preference. Spring applications help with moisture rentention and weed supression that is often needed the most in the summer.
For an easy way to sum it up:
- Apply initial mulch application at 3″-4″ depth
- Top dress new mulch layer 1.5-2″ once to twice yearly (preferably once only)
BAGGED VS. BULK
Mulches come in a both bagged and bulk loose forms. Where hardwood mulch most commonly comes in bulk, it also can be purchased in bagged forms, usually the smaller 2 cub.ft. bag sizes due to it’s heavier weight. Pine bark and cypress mulches most commonly come bagged and are most commonly found in the 3 cubic ft. sizes other than some mass merchants who utilize the 2 cub. ft. size to portray a lower price.
Bulk is typically the most economical way to purchase mulch but comes at the cost of a messier application as it needs to be manually scooped and transported throughout the landscape. You also need an open bed truck or trailers. Bagged mulches can be purchased and placed in both small vehicles and trucks and easily carried and placed at each area on site.
Evergreen of Colonial Height’s landscape and maintenance departments have found bagged forms of pine bark mulch to be preferred. Pine bark tends to be lighter than hardwood and takes less time to decompose. The surface of hardwood mulch discolors quicker than others has many gardener’s making more frequent applications. Hardwood mulches tend to decompose even faster when deeper layers are applied due to the increased heat and moisture retained due to the heavier application.
WEED BARRIER FABRICS
Weed barrier fabrics can be a great benefit to suppress weeds in the landscape, but there are a couple of things to remember to ensure their effectiveness. While weed barrier fabrics supress weed grwoth by covering the original soil – if organic debris/matter become layered or concentrated within the mulch layer on top of the weed fabric, then your weed problem is going to start developing above the weed fabric. We never recommend the use of plastics beneath mulches due to the lack of moisture and air flow that is blocked by the non permeable texture of the plastic. Most professional weed barrier fabrics contain a certain level of porosity that allows water and air flow to move thru the fabric. This is of utmost important to most trees, shrubs, and perennials.
I have found that, with hardwood mulches high decomposition rate, weed barriers are effective only for a short term and not worth the investment. We at Evergreen of Colonial Height’s only feel that weed barrier fabrics are only useful when applied beneath pine bark, cypress mulch, or other stone or gravel aggregates.
When applying weed control fabrics, manage smooth grading on the soil’s surface to make the application of mulch easier and more efficient. Overlap seams 3″-4″ and utilize U staples or weed barrier pins to manage the weed barriers attachment soil’s surface.