Updated at: 24-03-2023 - By: Sienna Lewis

Exactly when would be a good time to plant American marigold seeds in a greenhouse in Massachusetts? Before planting, it’s important to know when the danger of frost has passed, and you can easily keep track of this by marking your calendar eight weeks out. However, if you don’t have access to a greenhouse but still want to grow it outside, you can plant the seeds after the first frost.

But how does one determine the frost date of Massachusetts? Regardless of your state, every greenhouse grower must know the hardiness zone of their location. Massachusetts is in zones 5a to 7a, and you can use this to mark your calendar and determine the frost date.

Being hardy in temperatures between 3 and 11, American marigolds will do well in Massachusetts. These stunning flowers originate in Mexico and Central America, where they bloom in the spring, summer, and fall. African marigolds, also known as Mexican marigolds, are the world’s tallest and straightest marigolds.

When Can I Start Growing American Marigold Seeds In Massachusetts In A Greenhouse: Calendar For Planting

If you live in Massachusetts, you have time to start your marigold seeds indoors before the last frost date. Eight weeks ahead of time is possible, or fifty days. The University of Massachusetts at Amherst reports that the last frost date across the majority of the state is May 15.

When Can I Begin Growing Marigold Seeds In A Greenhouse? - Krostrade

Eight weeks before the last frost date

The seeds of American marigolds should be planted in a greenhouse eight weeks before the last frost, as was previously mentioned. You can pinpoint this time of year using the hardiness zone map of Massachusetts to find out exactly where you live. If you want to plant outside, though, you’ll have to wait until after the last frost, which is typically in the spring.

The last frost date in your area should be subtracted from the current date to determine when you should start your seeds. This is a recommendation made by the Massachusetts Master Gardener Association. If you want your marigolds to bloom sooner, you should start them indoors. However, the time it takes for these plants to go from seed to bloom is relatively short to begin with, so they can be sown outside after the threat of frost has passed.

Greenhouse gardening is more strategic because plants can be started indoors in relative safety. Keep in mind that the last frost in most of the Commonwealth of Massachusetts occurs around the 15th of May. With this information in mind, you can calculate how many weeks until you can move the marigolds into the greenhouse.

Fifty days before the last frost date

It’s best to start your marigolds indoors about 50 days before the last frost date, as this will give them plenty of time to mature before being planted outdoors in the middle of spring. By doing so, you can ensure that your plants reach the proper size without worrying about the effects of the weather outside. The germination time for the seeds is also very short.

After this occurs, it’s imperative that you give the plants at least 6 hours of light per day. Once a second set of leaves has appeared, the seedlings can be thinned. While waiting for the last frost date inside the greenhouse, transplant them into their pot.

Other Considerations For Growing American Marigold In A Greenhouse

When I find out when I can plant America marigold seeds in a Massachusetts greenhouse, other factors will determine how well they do. The time it takes for seeds to germinate, for instance, can be as short as 14 days. On the other hand, indoor temperatures should be kept between 65 and 75 degrees Fahrenheit, and the soil temperature should be between 70 and 75 degrees Fahrenheit.

If you’re planting seeds inside, you’ll need to do it in a warm, damp flower bed. If you plant marigold seeds now, you won’t have to worry about them blooming before frost for another 50 days. The soil’s pH should be between 6.0 and 7.0, so adding organic matter and monitoring it will help you get there. It’s recommended to leave 24 inches between rows of large marigolds, 15 inches between rows of medium marigolds, and 6 inches between rows of dwarf marigolds.

What Makes American Marigolds Different From Other Marigolds?

You’ll find that American marigolds, unlike other varieties, thrive when planted in the spring. This is due to their later maturity compared to, say, French marigolds. You can use these tall blooms as planting pockets or to bring color to the garden in front of shrubs.

If you want your beds and borders to stand out, plant some American marigolds in them. Herb gardens are often surrounded by a hedge of American marigolds. But which types would be ideal to grow?

Antigua Series, Jubilee Series, and Vanilla are some of the most well-known. American marigolds from the Gold Coin Series make great hedges.

Time of the Year to Plant Marigolds

In the genus Tagetes, commonly known as “marigolds,” you’ll find both annuals and perennials that are drought- and frost-tolerant. The height of these flowers can vary from 6 inches to 6 feet, and their colors can range from a very light yellow to orange, gold, and a brownish maroon. Marigolds can be grown in any garden because their seeds germinate quickly in warm soil. If you want flowers to bloom sooner, you can start the seeds indoors and then move them outside after the threat of frost has passed. In USDA plant hardiness zones 9 through 11, marigolds can be grown perennially.

When to Plant

There is no need to start marigold seeds indoors if you plan on planting them outside in the spring after the threat of frost has passed for your area. If the soil temperature is between 70 and 75 degrees Fahrenheit, seeds should germinate in four to fourteen days. Plant seedlings outside once frost risk has passed. The average time from planting to harvest for marigolds is 45-50 days.

How to Plant

Plant seeds in the flower bed, covering them lightly and making sure they stay warm and moist. Soil rich in organic matter is essential for successful transplants. Marigolds should be planted with a distance of 18 to 24 inches between large varieties, 12 to 15 inches between medium varieties, and 6 inches between dwarf species. In terms of soil conditions, marigolds thrive in organic-rich soil with a pH of 6.0 to 7.0, but they can also grow in arid environments.

Where to Plant

The sun is essential for marigolds, but in regions where summers are particularly scorching, they also appreciate a bit of afternoon shade. But too much shade can prevent blooming, so only use it if necessary. Marigolds can be used as a border plant or in flower beds. They thrive in a variety of conditions and can be grown successfully in containers on patios, porches, and balconies. Salvia, Zinnias, Nasturtiums, Gaillardias, and Bassias are all excellent companion plants for flower beds.

Marigold Care

Marigolds are low-maintenance flowers. Although the flowers can withstand dry conditions, they may benefit from watering if they are not blooming during periods of extreme heat. Pinch off faded blossoms to encourage new growth and extend flowering time. During stormy weather, staking is a necessity for taller varieties like African marigolds. Spittle bugs, spider mites, and aster yellows and wilts are just a few examples of common pests and diseases.

When and How to Plant Marigold Seeds | Gardener's Path

How to Plant, Grow, and Care for Marigolds

The marigold is the most upbeat and manageable annual flower. These blooms are the big spenders among annuals, showering our summer and fall gardens with metallic golds, coppers, and brasses. Bright blooms all summer long may contribute to the flower’s widespread acclaim. Deadheading is all that’s needed to ensure continuous flowering. Discover the details.

About Marigolds

Marigolds can produce single or clustered flowerheads that resemble daisies or carnations. There are roughly 50 species of marigolds, but most of the ones we see in gardens are:

  • African marigolds, American marigolds, or Mexican marigolds (Tagetes erecta): This variety of marigold grows to a height of 3–4 feet and has the largest, fullest blooms of any marigold. They are adapted to dry climates and can be found naturally only in Mexico and Central America.
  • French marigolds, or Tagetes patula, are typically more compact and smaller than their taller cousins, the Tagetes erecta. In most cases, they are wider than they are tall. They range in height from 6 inches to 2 feet, are visually appealing, and have refined, understated blooms. Like no other Tagetes species, these thrive in wetter environments.
  • These tiny marigolds, known as Tagetes tenuifolia, are great for use as an edging plant and thrive in hot, dry areas. Usually no taller than a foot at most.
  • Pot marigolds, or Calendula officinalis as it’s more commonly known, are a flowering plant in the daisy family. This “marigold,” originally from southern Europe, isn’t a true marigold, but it makes a lovely companion plant nonetheless. Edible and beautiful, its bright flowers are a welcome addition to herb gardens thanks to their tangy, peppery flavor.

When to Plant Marigolds

  • Planting time for young French and signet marigolds extends from early spring to midsummer, while the tall African marigolds should be planted as soon as the danger of frost has passed in the spring. Check here for your area’s frost dates.
  • Once the soil is warm in the spring, you can sow your seeds directly into the garden. Though seeds can be started indoors, there’s little point in doing so because they germinate so quickly once moved outdoors. However, African marigolds should be started indoors or purchased as young plants about 4 to 6 weeks before your last frost date.
  • In warm weather, marigold seeds germinate within a week, and flowering begins about 8 weeks later.

Choosing and Preparing a Planting Site

  • Growing marigolds in full sun is ideal, and they often survive scorching summers. Although the French marigold thrives in damp environments, the African and signet varieties can withstand dry spells.
  • Marigolds are susceptible to powdery mildew and won’t bloom as well if planted in shaded, cool, humid areas.
  • Marigolds can survive in almost any soil, but they thrive in moderately fertile, well-drained soil.
  • Dig down into it about 6 inches to loosen it up and get it ready. Get rid of the rocks.

How to Plant Marigolds

  • Although African marigolds can be grown from seed, the process can be time-consuming, so it’s recommended to buy young plants instead.
  • Slow-release (granular) fertilizer can be added to the planting hole if the soil lacks essential nutrients. It’s fine to use a 5-10-5.
  • Wet the ground and plant seeds an inch apart and no deeper than an inch.
  • Sort out the weaker seedlings while they’re still young. Put a good 8-10 inches of distance between French and signet fonts. African marigolds, particularly the larger varieties, need space of 10–12 inches between plants.
  • If you are using transplants, make sure to give each one a good soaking after you set it in the ground.
  • Use a potting mix that contains soil if planting in containers. At planting time, incorporate slow-release granular fertilizer, or schedule periodic waterings with diluted liquid fertilizer. Marigolds grown in containers require careful spacing to avoid suffocation.

How to Grow Marigolds

  • When the marigolds are well-established, pinch the tops off of the plants to make them fuller. Avoiding legginess and promoting increased flowering are both benefits of this practice.
  • Although deadheading isn’t strictly necessary for marigolds, doing so regularly will encourage the plant to produce abundant new blooms.
  • Allow the soil to dry out a bit in between waterings when caring for marigolds, then water heavily and repeat as needed. When temperatures are very high, you should increase your water intake.
  • Marigolds should not have overhead watering. Plant root zone hydration. (Powdery mildew develops when leaves are soaked for too long.)
  • Marigolds should be grown without fertilizer. Too much nitrogen in the diet promotes lush foliage at the expense of flowers.
  • African marigolds are susceptible to rot in wet conditions due to their dense, double flowerheads.
  • It’s important to use mulch between seedlings and established plants to prevent weeds and retain soil moisture.

How to Deadhead Marigolds

By pinching off the flower head, deadheading removes spent blooms from a plant. By removing spent blossoms from plants like marigolds, you can extend their flowering period and prevent the plant from putting its resources toward seed production. Deadheading can also dramatically improve the appearance of marigolds.

Marigolds are among the simplest plants to deadhead. Pinch the stem of a wilting flower until you reach the nearest set of leaves.

Deadheading annuals is a great time to fertilize them. As annuals, they are heavy feeders and will thrive with this treatment.

Overall, spider mites and aphids are the worst enemies of a marigold garden. The problem can usually be solved by spraying the area with water or applying an insecticidal soap every other day for a week or two. Powdery mildew, a fungal disease, can occasionally affect marigolds if the environment is too damp. Keep weeds at bay, plant in well-drained soil, and water the soil rather than the marigolds to prevent fungal problems.

Marigolds as Companion Plants

It’s common knowledge among farmers and gardeners that marigolds are useful companion plants for a wide variety of other plants.

  • The underground structures of the French marigold are especially effective at deterring nematodes (microscopic worms) like root-knot and lesion nematodes, which feed on the roots of garden vegetables. Tomatoes, cucumbers, strawberries, snap beans, squash, onions, and garlic are among the worst-affected crops.
  • Don’t put marigolds in with your vegetables if you want to take advantage of this. Instead, you should plant a large quantity of marigolds in the spring in the area where you will be growing your fall crop. Get rid of the marigolds in the middle to late summer, and replace them with fall harvest vegetables and greens.


Large and small, yellow marigolds can be found in a spectrum of colors, from pure white to bright orange. In general, French marigolds are more diminutive than their American and African counterparts.

French Marigolds (T. patula)

  • The ‘Little Hero’ Series consists of 7-inch-tall plants that bloom a wide variety of maroon, orange, and yellow double carnation flowers.
  • The ‘Hero’ Series boasts 10-inch-tall plants with large, double carnation flowers measuring 2 inches across and available in a spectrum of bright yellows, oranges, and maroons.
  • ‘Bonanza’ Series: compact 8″ tall bushes covered with 2″ wide double carnation flowers in 5 colorways of yellow, orange, and maroon.
  • Plants in the ‘Aurora’ series reach only 1 foot in height, but their anemone-like flowers come in a range of vibrant colors, from deep maroon to bright yellow and orange.
  • Series about a girl named “Janie”; she matures quickly. The ideal plant height for growing in a container is 8 inches. Flowers resembling double carnations, available in six colorways of yellow, orange, and maroon.
  • Plants in the ‘Boy O’ Boy’ series bloom profusely and reach a height of 6 inches, with colorful blooms in maroon, yellow, and orange.

American/African Marigolds (T. erecta)

  • Plants in the ‘Jubilee’ series grow to a height of 2 feet and bloom double, orange and yellow flowers.
  • Plants in the ‘Gold Coin’ series grow to a height of 1.5 to 2 feet and produce large, double flowers measuring 5 inches across.
  • Plants in the ‘Safari’ series grow to a height of 1 foot and produce large, flat-topped blooms in maroon, yellow, and orange.
  • The flowers of ‘French Vanilla’ are three inches wide and a pure, milky white color. Small odor production. Growing to a height of 1.5 – 2 m.


  • You can prevent a flower arrangement from smelling too strong by removing any leaves that will be submerged in water.
  • Dried marigolds make beautiful, long-lasting bouquets. Remove stems and leaves from flawless flowers, then suspend them upside down.
  • The name “marigolds” appears on some lists of edible flowers. Calendula flowers, rather than Tagetes, are a better choice for spicing up a summertime dish. We advise against eating the flowers of the Tagetes marigold plant due to the risk of skin irritation.


  • David Burpee, president of Burpee, led a vigorous campaign in the late 1960s to have marigolds named the national flower, but roses ultimately prevailed.
  • Farmers have been using the open-pollinated African marigold ‘Crackerjack’ to dye egg yolks for years.
  • One of October’s birth month flowers is the marigold.


Unlike Calendula, which has edible flowers, Tagetes marigolds do not. Calendula’s vibrant petals brighten salads and other summertime fare while also lending a spicy flavor.

  • The color (but sadly not the flavor) of saffron can be imparted by cooking the flower petals with rice.

How Often Do You Water Marigolds?

Marigolds (Tagetes patula) are one of the few annuals that never fail to brighten a room. These hardy plants begin blooming in early summer and keep going strong all the way up until the first frost if you just pinch off the spent blossoms. They’re great for luring in winged creatures like butterflies and hummerbirds. At the very least once a week, give your marigolds a good soaking.

When and How to Plant Marigold Seeds | Gardener's Path

About Marigolds

Marigolds, which can be found growing wild from New Mexico to Argentina, have been a garden mainstay for decades. Bushes can be as short as 4 inches or as tall as 6 inches. Although these fragrant annuals can be grown successfully from seed, most gardeners opt to purchase started plants at the beginning of the growing season. There are yellow, orange, red, white, and even bicolored flowers to choose from. Marigolds come in a wide range of sizes; shorter ones are ideal for container gardening or edging, while their taller cousins are excellent for use as cut flowers.

Cultural Needs

For optimal growth and blooming, marigolds require full sun and soil that is both rich and well-drained. The plants can survive mild drought, but their flowering is stunted as a result. Use potting soil rather than garden soil for growing marigolds in containers because garden soil is too heavy and dense. Marigolds can be kept blooming until frost if deadheading, or removing the spent flowers, is done regularly. Apply fertilizer consistently, following the recommendations on the packaging.

Watering New Plants

Marigolds need a lot of water right after planting to settle the soil and hydrate their roots. Until the plants are well-established, keep the soil around their roots moist but not soggy. It takes about a week and a half to do this.

Watering Established Plants

Marigolds need a weekly deep watering once they are established in garden beds. Water them sufficiently to soak the top 6 to 8 inches of soil. They will need more water if the temperature is high or the wind speed is high. To care for marigolds in containers, water them when the top inch or two of soil is dry. In hot weather, marigolds may stop flowering, but giving them a good soaking will usually get them to start blooming again.

Fertilizer Precaution

Any plant, including marigolds, can suffer chemical burns from fertilizer if it is applied to dry roots. The day before you fertilize, make sure to give your plants a good soaking. This includes fertilizers that dissolve in water.


When should I start seeds indoors in MA?

When should I start my seeds indoors? It depends on the type of plant and when the last frost is expected in your region. The date of the last frost in many parts of Massachusetts isApproximately on or after May 15Estimate how many weeks until the recommended transplanting date for each vegetable.

What conditions do marigolds grow best in?

Marigolds are a low-maintenance plant that grows quickly once planted. Most plants can tolerate direct sunlight and even thrive in it. As long as they are given enough water, marigolds can thrive in the intense heat and light that is reflected off of asphalt and concrete. Marigolds, on the other hand, can survive in as little as 20% shade, provided they get plenty of light during the rest of the day.

Do marigolds come back every year?

Are Marigolds Annuals That Always Return? Annual marigolds are the most common type used for gardening. They have a complete life cycle of germination, blooming, and perishing in a single calendar year. The flowers’ ability to self-seed, however, usually ensures their return the following year.

Which month is best for growing marigold?

Marigolds should be planted in the spring. After the last spring frost, plant marigolds in your yard. If you plan on starting your plants indoors from seed, you should do so about two months before the last frost. In warm soil, between 70 and 75 degrees Fahrenheit, seeds germinate in 4 to 14 days.

Do marigolds do well in pots?

The only limitation to growing marigolds in containers is the size of the container itself; some varieties, like African marigolds, can grow to be over 3 feet (1 m) tall. Miniature marigolds grown in pots are a popular choice for gardeners.

How long do marigold plants last?

Since they only live for one growing season, garden marigolds must be planted, germinate, grow, flower, and then die. Even if started indoors at the beginning of the year rather than in the garden from seed, their maximum lifespan is typically less than a year.

When can you plant marigolds outside?

Seeds of marigolds can be planted outside in the spring once the threat of frost has passed in your area, or they can be started indoors up to about eight weeks before the last frost. When planted in soil at 70–75 degrees Fahrenheit, seeds typically germinate within four to fourteen days.

What to do with marigolds at the end of the season?

For example, if the temperature drops below freezing in the late fall, annual marigolds will perish. After marigolds have died completely, cut them back to the ground with sharp shears or pull them up by the roots. Gather up the trimmings and store them away for the winter to prevent pest infestation.

Do marigolds attract bees?

Choosing a variety of marigold with an open center ensures that pollinating insects will have no trouble locating the bright yellow flowers. The little ‘Gem’ marigolds that fit the bill aren’t as long-blooming as the French marigolds that are the bees’ and butterflies’ top choice in my garden.


Flowers thrive in the climate and soil of Massachusetts. You may wonder, “When can I start growing American marigold seeds in Massachusetts in a greenhouse?” because American marigolds are a common variety. Your seedlings should be planted eight weeks or fifty days before the last frost date.

Knowing your location’s hardiness zone will aid in pinpointing when the last frost is likely to occur. Massachusetts has a range of hardiness zones from 5 to 7, but the last frost date is typically around May 15th. As a result, you should double-check your seasons to avoid problems.