There has been a lot of discussion about using black plastic in vegetable gardens. Those that use it will list the pros, those that don’t will list the cons. Let’s face it … it’s all about preference and what works for the gardener.
Before making a decision on whether to use black plastic in your vegetable garden, why don’t we look at the pros and cons of using this type of mulching instead of an organic mulch. The information shared may help you decide whether black plastic is or isn’t the mulch to use.
What And Why Do You Use Black Plastic?
Black plastic is used as a type of mulching in gardens to prevent weeds from growing. It is plastic film and/or sheets that come in different lengths, widths and thicknesses. You can purchase it in agricultural stores, nurseries, and even online.
Black plastic sheeting or mulch has been used since the 1950s. Nowadays this plastic sheeting comes in a variety of colors, however, black is still the most popular and the cheapest.
They even have a biodegradable black plastic mulch, which is very thin and may be difficult to work with in windy environments.
It’s important to note, that if you choose a sheeting that is very thin, you will more than likely have to replace it every season. Whereas, a thicker plastic sheeting may last up to two years.
Pros Of Using Black Plastic Mulch …
Here is a list of some of the benefits of using black plastic mulch and then the reasons why some gardeners prefer it.
Warms the soil
Controls soil moisture
Reduces soil erosion
Reduces spread of diseases
Encourages better yields
Reduces/kills weeds – This is one of the top benefits of using black plastic sheeting. Weeds cannot grow or thrive in the dark and with the addition of heat, it’s a win-win situation.
If this is your first gardening attempt, this would be the perfect way to eliminate weeds and prep the soil for planting.
Warms the soil – Certain vegetables thrive in warm soil. Using black plastic mulch to increase soil temperatures can accelerate growth and encourage seeds to sprout faster.
Controls soil moisture – Evaporation will occur at the openings where the vegetables are growing.
By using black plastic mulch, the covered soil remains moist which is beneficial for the root system and excess water can run off the sheets preventing plants from drowning.
Reduces soil erosion – Using black plastic mulch helps reduce the soil from compacting, helping it to be well-aerated and loose, hence reducing soil erosion.
Reduces spread of diseases – Since the plastic sheeting is covering most of the ground, the vegetable plants foliage does not come into contact with the soil from its tiny opening, helping to prevent the spread of diseases from the soil or roots.
Encourages better yields – Weeds are no longer a nuisance and are not competing for the soil’s nutrients and/or additional fertilizer that will benefit your vegetables growth and provide better yields.
Another thing to consider is the look of your garden. If you are a neat freak, then using black plastic mulch is an attractive way to make your garden look nice, clean and uniformed.
Cons Of Using Black Plastic Mulch …
Let’s look at the reasons why some gardeners choose not to use black plastic sheeting/mulch.
Not good for all veggies
More time planting
Can get costly
Hot and slippery
Watch the wind
Not good for all veggies – As we discussed above, black plastic mulch is good for veggies that love warm soil, so the opposite holds true. “Cold season” veggies grow better without the plastic which if used could scorch plants.
And those with long roots would not get enough water since the plastic on top of the soil is preventing the water from being absorbed.
There is also the possibility of vegetables contacting diseases or funguses from contained water that does not evaporate.
Cooler areas – Using black plastic mulch in cooler and/or cold areas may not be sufficient in ridding your soil of weeds and/or pathogens.
More time planting – There is a little more work involved then digging a hole and dropping seeds in.
It is time consuming because you want to keep the plastic sheets intact except for the opening/hole needed for each seed.
Can get costly – Depending on what you are growing, your cost may increase due to the need to add fertilizer, drip tape, and/or drip tube irrigation, which will need daily monitoring.
Plastic does not break down and should never be “tilled” into the soil, unless it is the biodegradable plastic mulch.
Being said, anything plastic including sheeting, should be removed and disposed of at official sites.
Hot and Slippery – You already know that the black plastic sheeting absorbs heat, so touching or walking on it can sometimes be too hot to handle.
This is the perfect excuse to garden early in the morning or later in the evening when the sun is going down or on cloudy days.
Overcast or rainy days may be appealing, but think again! That wet plastic sheeting is a slippery accident waiting to happen.
Watch the wind – If you haven’t used black plastic sheeting/mulch before, it’s important to know that the thinner it is, the more likely it will lift up, fly or move with just a little gust of wind. Even thicker plastic can lift up and move if there is a significant windstorm.
So, laying black plastic sheeting definitely needs to be done on days that are not windy. Heavy weights, such as bricks, concrete blocks, even rocks should be available to hold down the edges.
The Bottom Line
The decision to use black plastic sheeting/mulching is up to you. You can weigh the pros and cons, talk to other gardeners, and/or do more research. I will tell you that I have used black plastic mulch at the very start of making a vegetable garden.
It was a fast way to deal with weeds and prep the garden for spring time planting; I would probably do the same if I was to start another garden. However, now that the garden has been established, I opt for more organic biodegradable types of mulch. So ultimately, the choice is yours … yes, no or maybe a little. Happy gardening!