When is the best time to plant vegetables? Is it spring, summer, fall or winter?
When staring your own vegetable garden it is very important to know when you should plant, grow or harvest your vegetables.
Getting the growing seasons right is crucial otherwise you may sow seeds or plant your vegetables and not see them grow.
In this article, I’ll explain the different things that go into deciding that to grow during what time of the year based on where you live.
In this section, you’ll learn all about climate and how it affects your garden.
That said, climate isn’t just one thing. It’s influenced by many factors. As such, you’ll be learning about the different things that affect climate. And, what they mean for your garden.
What Does Growing Season Mean?
Simply put, the growing season is the time of year when the climate, including temperature and rainfall, are favorable for growing plants.
More specifically, your growing season starts from the last frost in spring (average date of last frost) all the way to the first frost in fall (average date of first frost).
Just as importantly, the number of days in your growing season gives you an idea of how long these conditions are in your area to allow for plants to grow to maturity.
It’s worth noting that depending on where you live, the growing seasons will vary. For example, in different parts of the world, spring, summer and winter come at different times of the year.
In Australia, summer runs from December to February. But, for the U.S., that’s wintertime.
Similarly, if you live in California, Arizona and parts of Florida, you don’t have to bother about winter since there’s sunlight all-year-round.
Plant Hardiness Zones
One of the things you’ve likely noticed at the back of your seed packages is the colorful map. These are plant hardiness zone maps. In most cases, they’re the same map. But, depending on the manufacturer, the map they choose may differ.
Plant hardiness zone maps tell you which plants are best suited for your location. And, each country and/or region has its own version.
For the U.S., it’s the USDA Plant Hardiness Zone Map. Canada has its own and so does Australia.
The USDA Plant Hardiness Zone Map divides the entire country into 11 different zones. Each zone is identified by its average minimum (lowest) temperature.
This way, you’ll be able to tell whether a specific plant can survive the most extreme temperature your area experiences during the winter.
If it can, then it’s “hardy” to your location (or zone). In general, a plant’s hardiness tells you how well it can tolerate cold temperatures.
That said, zones are divided in a way that each one is 10 degrees colder (or warmer) than the next higher (or lower) zone, with the lowest zones being the coldest while the highest-numbered zones being the warmest.
In some cases, zones are divided into sections “A” and “B”, where the temperature in each zone varies by 5 degrees Fahrenheit.
How Do You Use the USDA Plant Hardiness Zone Map?
The goal here is to find what zone you live in. You can use your ZIP code or locate your state in the map. This allows you to know what the average lowest temperature your area gets during wintertime.
That way, you’ll be able to tell whether you can grow that specific plant in your garden.
In general, plants don’t like the cold. Most of them die during the winter with others “running for cover” so they can return when the spring sunshine comes around.
As such, trying to grow plants that can’t withstand the frost or freezing temperatures in your city can be frustrating.
This is why seed packages include that information. By doing so, you can quickly tell whether the plant is suited for your city.
That said, it’s important to note that plant hardiness zone maps only consider 1 variable, the temperature. It doesn’t consider microclimates which can improve your chances of growing a plant out of your zone.
Using Plant Hardiness to Plan Your Vegetable Garden
The other part of the plant-climate equation is your plant. In addition to all the complexities of climate, it’s also important to understand that different plants are designed to tolerate various kinds of climates.
As such, it’s important to know which vegetables you can safely plant in your locations. Additionally, at what dates you’ll be able to do so, such that they don’t end up dying on you.
To help you sort through that, one of the ways plants are categorized is by their hardiness. Or, their ability to grow well in specific times of the year.
- Very hardy. Vegetables that are considered very hardy are those that can withstand both frost and extreme cold. These include cabbage, cauliflower, kale, lettuce, garlic, onion, mint, thyme and peas among others. As such, you can plant them 4-6 weeks before the average date of last frost. This allows them to “get a head start” to the new season.
- Hardy. These vegetables are a notch lower than their very hardy counterparts. But, they’re still very tolerant of cold weather. As such you can start planting them about 2-3 weeks before the average date of last frost. Some veggies that fall under this group include celery, chard, carrots, parsnips, radish, turnip, parsley, oregano, beets, fennel and rosemary among others.
- Tender. Vegetables that don’t like the cold are called tender. Thus, they prefer to be planted when last frost occurs. While it’s later than the more hardy vegetables, it also allows them to enjoy the warmer climate that they thrive in. A few examples include tomatoes, corn, sage, dill, basil and most beans.
- Very Tender. Vegetables that can’t tolerate the cold fall under this category. Thus, you’re better off waiting till spring before planting or 2-3 weeks after last frost. That way the weather (and soil) has warmed up to their liking. You can say that these are the most delicate ones as far as cold and frost as concerned. Some examples are tomato, cucumber, squash, peanuts, pepper, okra, and pumpkins. As you can guess, these are mostly warm-season vegetables (see below for more on them).
Here’s a chart showing vegetable seed germination in case you want to start them from seed.
It includes frost tolerance (tender or hardy), ideal soil temperature for germination, days to germination and days to maturity per vegetable.
First and Last Frost Dates
Frost dates are one of the most important things to know in vegetable gardening. These are the average dates of the:
- Last frost in Spring
- First frost in Fall
These dates are essential because they affect your crops in many ways. These include:
- Tells you when you should start planting
- How long your growing season will be.
- When you need to start protecting your warm-season vegetables.
Here’s how extreme cold temperatures affect plants
- 29 to 32 degrees Fahrenheit = Light Freeze. This is enough to kill tender plants
- 25 to 28 degrees Fahrenheit = Moderate Freeze. Will likely destroy most vegetation
- 24 degrees Fahrenheit or lower = Severe Freeze. Will cause heavy damage to most plants.
It’s worth noting that frost dates are not meant to be precisely accurate. They’re averages. So, the actual dates may come slightly before or after the listed dates.
In any case, it gives you a good idea of when to start monitoring.
This is why it’s a good idea for gardeners to keep tabs on the weather forecast. Because they’re more short-term in nature. As such, they’ll be able to more accurately tell you when the exact dates are for any given year.
Sunlight, Temperature & Rain: Important Factors That Affect Climate
We’ve already discussed sunlight in-depth above. So now, it’s time to focus on the other two factors, temperature, and rain.
Most vegetables do well between 40 to 85 degrees Fahrenheit. For the most part, plants grow faster during warm temperatures. And, they’re growth slows down or stops in cold times.
As such, high and low temperatures both affect how your crops grow.
But, they can produce unpleasant results as well.
For example, when the temperature gets too high or too low, leafy vegetables like lettuce and cabbages may be forced to prematurely flower. As such, not producing enough foliage which they were meant for.
Similarly, night-time temperature is usually 5 to 10 degrees lower than day time. But, there are periods during the year when temperatures can significantly drop or be cold enough that some crops may suffer. Peppers are an example of this. And, when that happens, you can expect harvest to be thinner that season.
That said, different vegetables have varying temperature tolerances. Some like the cold, others like it warm.
- Cool-season vegetables. Crops like peas, cabbage and lettuce prefer cooler temperatures. Thus, you should grow them when it’s still chilly so that they mature before it gets warm. If you grow them too late, the hot temperatures will cause them to wilt or go to seed without producing foliage. Is a cabbage still a cabbage if it’s only got a few leaves?
- Warm-season vegetables. Crops like peppers, tomatoes and cucumber prefer warm weather. They don’t do well in the cold or when there’s frost. Both of which will either make them produce lower yields or yield nothing at all.
We’ll discuss more about cool and warm season crops below.
In any case, here’s a chart that shows you cool season vegetables, warm season vegetable and perennials.
Microclimates happen when your climate conditions are different from those of nearby areas surrounding you. The differences are often caused by natural or man-made objects that are surrounding your area.
For example, if you live in an area that’s surrounding by buildings or hills, you’ll likely experience more shade (less sunlight) because these large structures block the sun.
Similarly, if you live by a large body of water, the climate will be cooler during the summers and warmer during the winters compared to the neighboring town.
Microclimates play a big role in gardening because they alter the conditions in your yard. As such, the climate you experience isn’t always the same as that in your city or region.
Just as importantly, by creating your microclimates you can somewhat offset the climate in your area to make it favorable for growing certain plants.
A few examples that can affect or cause microclimates.
- Low areas like valleys. Expect colder temperatures since cool air is heavy. Thus, they’re prone to frosting more during wintertime. And, expect the soil to be wetter during that time of the year as well.
- Living near large bodies of water. Water doesn’t heat up or cool down as quickly as the ground. As such, if you live near a lake or ocean, you’ll stay cooler during the summer and feel warmer during the winter compared to other places that don’t have the benefit of being near a body of water.
- Slopes and inclines can increase the risk of erosion. Plus, if you live above the equator (like in the U.S), south-facing slopes dry up and get warmer faster compared to north-facing slopes.
- Presence of buildings, walls and other structures. These structures help keep you warm and protect you from strong winds (although they can funnel strong winds as well). They also provide relief from the overly intense sun during hot summer afternoons.
- Open areas. You’ll be able to get more direct sunlight, which makes them perfect for plants like that full sun. But, they also don’t get any protection from the rain, snow and intense heat when they occur.
- Tall trees, hedges, bushes or shrubs. Besides privacy, these plants provide protection from strong winds and an overall better microclimate for growing plants and vegetables. But, they also reduce the amount of light your garden receives since they block sunlight and cast shadows.
These are just some examples of how microclimates can form depending on your location and the surrounding environment.
The good news is, you can plan your garden according to what’s there. And, you can modify it to increase your garden’s yield.
When and how much rainfall your garden receives also affects how your vegetables grow. Rainfall plays a major role in your vegetable garden’s growth primarily because plants need water.
And, just like the sun is the best source of light for your crops, rain is also the best source of water for them.
But, depending on where you live, it’s likely that you may experience more or less rain, each of which brings their own pros and cons.
- Too much rain causes the same results as overwatering. Thus, damaging or even killing your crops. Also, it can also wash away seeds and seedlings, not to mention potentially cause soil erosion. During a plants’ flowering stage, consistent rainfall can decrease yields as well as pollination. Plus, rain also increases the risk of pests and disease.
- Too little rain can lead to drought. Even when it doesn’t get to that point, low amounts of rainfall slows down overall growth. If it continues for prolonged periods of time, it can damage or kill your crops as well.
The biggest difference between the two is that you can remedy too little rainfall. As long as your garden isn’t overly huge, you’ll be able to water it more.
But, if there’s too much rain there’s little you can do to prevent the rain from overwatering your plants. That is unless, you have some sort of retractable roofing to cover your plants. And, even then, you’ll still need to figure out how to provide them with enough light.
When to Plant Vegetables
Spring is the best time to plant most vegetables, but not all of them.
That’s because the warm weather and sun will help them grow faster and let you get your harvest sooner.
However, a big factor that will help you figure out when to plant your vegetables is how hard those crops are.
The more cold hardy they are the earlier you can begin.
Below is a chart showing when you plant your vegetables in spring. It groups the vegetables by hardiness.
And will tell you how many weeks from last frost date can you begin planting.
In case you decide to start your vegetables indoors to get a head start, here’s chart that shows how easy or hard it is to transplant different kinds of vegetables.
This way you can decide whether to start indoors or just wait for the warmer weather to arrive and plant directly outdoors.
Planting Vegetables in Pots
Just in case that the weather in your area does not cooperate making it hard for you to grow some of your favorite veggies in the backyard, you can do so in containers.
Here’s a chart of how to grow vegetables in pots or containers.
It includes how much sunlight each of the veggies need, the minimum container size and the spacing between plants when planted in the pots.
The chart also gives you an idea of how many days from seed to harvest so you can plan ahead.
When to Side Dress Vegetables in the Garden
Side dressing your vegetables is an important part of growing a vegetable garden. This ensures that they get the nutrients they need to grow optimally.
This chart tells you when to side dress different kinds of vegetables.
When Should You Harvest Vegetables?
Just as it is important to know when to plant vegetables, it is also important to know when to harvest them.
After all, you don’t want to harvest them prematurely. Nor do you want them to do so long after they’re optimal harvest dates.
Here’s a chart that shows when to harvest each type of vegetable. It includes the days to maturity and what to look for to know when to harvest.