Can you even have a vegetable garden without marigolds? I say not. Here is how and when to plant marigold seeds indoors.
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In past years, I have always gone to my local greenhouse or garden centers to buy marigold plants. However, once you realize that starting marigold seedlings at home makes more sense when you are planting vegetable seedlings anyway, then it’s time to get started. That must be where you are. Are you wondering when to start marigold seeds indoors? Now, it’s time to start these yellow and orange flowers at home.
When to Start Marigold Seeds indoors?
Marigold seed packets will tell you when to start marigold seeds indoors. About 4-6 weeks before your average last frost date. Personally, I have found the 6 week mark to be better than the 4 week mark. Even doing them up to 8 weeks before works amazing! However, don’t let that stop you from planting if you are 4 weeks out from your average last frost date!
Late winter and early spring is not only the perfect time to start a lot of seedlings, but there are some other garden tasks you can do as well, even if you can’t actually be planting vegetables or flowers yet. Check out 10 ways to prepare your garden for spring.
Average Last Frost Dates by Zone:
- Zone 1: May 22-June 4
- Zone 2: May 15-22
- Zone 3: May 1-16
- Zone 4: April 24-May 12
- Zone 5: April 7-30
- Zone 6: April 1-21
- Zone 7: March 22-April 3
- Zone 8: March 13-28
If you are direct sowing marigold seeds into the ground, go ahead and direct sow seed after any chance of frost.
Why would you start marigold seeds indoors?
In some places, you can direct sow marigold seeds straight into the ground. If your growing season is long enough, go ahead and direct sow. However, in zone 4, where I am, I need to get a head start on the growing season. So, for a little effort, I start my own marigold seeds.
How to start marigold seeds indoors:
Fill seed tray or a cup drilled with drainage holes with moistened seed starting mix.
Place seeds about a quarter of an inch the way down into the soil. If using an older seed packet, plant 2-3 flower seeds per cell. Marigold seeds are really light, so be aware when you go to dump them out of the packet.
Spray the top of the soil with water from a spray bottle.
Cover with plastic wrap to help with germination. Typically, seeds will germinate within a week. To speed up germination, place in a warm location.
After germination has occurred, remove the plastic wrap and place in a sunny spot or under grow lights. Depending on where you live, there might not be enough hours of direct sunlight so building a DIY seed starting shelf might be helpful to make sure these cheerful flowers get enough light.
Make sure to keep these young plants watered but not over-watered. Watering from below is not only easier but will help prevent damping off.
Hardening off marigolds:
After any danger of frost has passed, it is time to move marigold flowers outside. First though, you need to harden off the marigolds so that they don’t die of shock. Start by placing flowers outdoors for a few hours each day in the shade. After a few days of gradually increasing time, leave them outside all day but bring them in at night.
Marigold flower beds should be in full sun and in well-drained soil. If there will be a cloudy day in your forecast, try to transplant on those days. It helps acclimate the marigolds better so there isn’t quite as much stress from the constant heat from the warm weather.
Dig a hole about the size of the ball of roots and place the marigold into the ground. Fill in the hole around the roots with soil. Plant about 10-12 inches apart.
Add a layer of mulch to keep weeds down.
After planting, water around the base of the plant. For best results, water the new plants daily for a week.
Now, you can sit back and enjoy the bright color of these annual flowers!
Benefits of Marigold Flowers in a Vegetable Garden
Planting marigold flowers in a vegetable garden isn’t just pretty, it is actually smart. Marigolds attract beneficial insects such as bees and other pollinators. Evidence has also been found that marigolds even repel insects that could harm your garden!
Planting marigold flowers near tomatoes is a strategic move. Marigold flowers repel nematodes, slugs, and tomato hornworms that will eat your tomatoes so use marigolds as companion plants.
Tips for Growing Marigolds in a Vegetable Garden
Marigold flowers are actually some of the easiest flowers to take care of once they are in your garden. However, here are just a few bonus tips for you.
- Do not over water. These flowers don’t like too much water, so it is better to under water than it is to give them too much.
- Adding mulch around the base of the plant will keep weeds down and keep the flower hydrated, requiring you to water even less.
- After planting, marigolds do not require fertilizer as they are low feeders. Too much fertilizer will cause the plant to produce fewer blooms as it devotes its energy to foliage growth.
- When the flower heads are dead, remove them. This encourages more flowers. Removing the dead heads can also save you money on flower seed for next year. Keep the dried, dead flower heads and use the high-quality seed you just grew yourself for the following year! Store in a cool dark place.
Varieties of Marigold Flowers
There are three main types of marigold flowers. These marigold types are:
- French marigolds, or Tagetes patula, these have an average height of 12 inches
- African marigolds, or Tagetes erecta, these have an average height of 3 feet
- Signet marigolds, or Tagetes tenuifolia, these have an average height of 12 inches
There are a whole bunch more species of marigolds than just these three, but those are the ones you will see most often.
Marigold seeds can germinate in light or dark. The temperature is what actually matters for germination. To speed up marigold seed germination, place in a warm location or on top of a heating pad.
Marigold seeds do not need to be soaked before planting. However, soaking them in warm water for an hour can possibly speed up germination time.
The pointed end of the marigold seed goes down into the soil.