Starter seeds are starter plants that you start growing indoors before transferring them outside. You might want to buy starter plugs or starter pots, which add a starter plug or starter pot to each cell in the starter tray for all your seedlings.
Why Do You Need Starter Seeds?
You might need starter seeds when you want to grow vegetables from seed or if you don’t have a green thumb. You can start your starter seeds directly in the ground after all danger of frost has passed, but this is risky and somewhat impractical. For safety, most people start their starter plants indoors and then move them outside once they’ve grown large enough to survive on their own. This gives the young starter plants more time to put down roots and get used to life outside before winter comes around again.
Many people who would like to garden fail at growing vegetables because of poor timing. If they plant out into the garden too soon, then they run the risk of transplant shock or pest infestation that will kill their vegetable garden. A good way to avoid these pitfalls is by starting your starter seeds indoors so you can give them some extra time before being planted out in the garden.
How Would You Start Starter Seeds Indoors?
To start starter seeds inside, first, put a starter plug or starter pot into tray or starter cells on a seedling mat. Put about 3 inches of water on top of the starter plug and let it absorb for at least 10 minutes. Add starter soil to cover starter plug and tap gently with a spoon handle to settle soil around starter plant plugs. Water lightly until evenly moist but not drenched. Plant vegetable seeds as directed on the seed packet (see Resources below). Cover seed row with clear plastic wrap, pushing down around each plant; this will help keep the temperature inside the starter tray warm. It may take up to five days for the starter seeds to germinate.
When Should You Start Starter Seeds Indoors?
Start starter seeds indoors 8-10 weeks before transplant date, or about 6 weeks before the last frost of spring. Gardeners in southern regions of North America can start their starter plants 6-8 weeks before the transplant date while gardeners in northern areas will need 8-10 weeks for starter plant growing time.
Which Vegetable Seeds Should Be Started Indoors?
Here is a list of vegetables that you can grow from seed, and how long it takes them to sprout when started inside:
Beans – 3-5 days (Runner beans are more susceptible than bush beans.)
Brussels sprouts – 9-10 weeks (Start Brussels sprouts outdoors in starter plants.)
Cabbage – 4-5 weeks (Start cabbage starter plants outdoors after danger of frost has passed.)
Celery, Chinese, or cutting celery (celeriac) – 12 weeks (Celeriac starter plants take longer to grow than regular celery starter plants.)
Chinese cabbage, Napa, and other Oriental cabbages – 5 weeks
Corn – 2-3 days (in warm weather, wait for seedlings to be out of before planting outside; corn is usually planted in starter plants.)
Cucumber – 6-10 days (Use starter plants to reduce transplant shock; not all cucumbers are started indoors. Shift starter plants to larger containers for growing after they’ve reached 2 inches tall.)
Eggplant – 6 weeks (Shift starter plants to larger containers for growing after they’ve reached 2 inches tall.)
Leeks – 9-14 weeks (Start leek starter plants outdoors in starter plants or seedling trays—they don’t like to be transplanted once they’re established.)
Lettuce, head or leaf – 10 days (Leaf lettuce is more sensitive than head lettuce when it comes to light exposure and temperature changes during seedling growing time; starter plants are recommended for seedlings since they’re more likely to survive the transplant shock.)
Melons – 2-3 days (Use starter plants or seedling trays to reduce transplant shock. When planting outside, wait until the ground temperature reaches at least 60 degrees F.)
Okra – 5 weeks (in warm weather, wait for seedlings to be out of before planting outside; okra is usually planted in starter plants.)
Onions, bulbing – 9 weeks (Start onion starter plants outdoors after danger of frost has passed. Transplant outdoors when bulb gets to pencil size.)
Parsnips – 12 weeks (Start parsnip starter plant outdoors after danger of frost has passed.)
Peas – 3-5 days (Use starter plants or seedling trays to reduce transplant shock. When planting outside, wait until ground temperature reaches at least 60 degrees F.)
Radishes – 1 week (Start radish starter plants outdoors after danger of frost has passed.)
Spinach – 7 days (Use starter pot or starter cells on a seedling mat; do not use starter plug; plant seeds directly into starter soil without covering with starter soil since spinach seeds need light to germinate. Cover starter pots with clear plastic wrap and keep covered until the first leaves appear.)
Squash, summer – 10 days (Shift starter plants to larger containers for growing after they’ve reached 2 inches tall; squash is usually planted in starter plants.)
Squash, winter (pumpkin) – 6 weeks (Shift starter plants to larger containers for growing after they’ve reached 2 inches tall; squash is usually planted in starter plants.)
Swiss chard – 7-14 days (Use starter pot or starter cells on a seedling mat; do not use starter plug; plant seeds directly into starter soil without covering with starter soil since Swiss chard seeds need light to germinate. Cover starter pots with clear plastic wrap and keep covered until the first leaves appear.)
Tomato – 10-12 days (Move up to larger holding pots every few days if using Jiffy pellets for starting tomato seeds indoors. )
Turnips – 5-6 weeks (Start turnip starter plants outdoors after danger of frost has passed.)
Watermelon – 6 weeks (Shift starter plants to larger containers for growing after they’ve reached 2 inches tall; watermelon is usually planted in starter plants.)
Zucchini – 10 days (Shift starter plants to larger containers for growing after they’ve reached 2 inches tall; zucchini is usually planted in starter plants.)
Starter Seeds Indoors vs. Outdoors
You can start most vegetable seeds indoors. You can do this by planting them into starter soil or into starter cells on a seedling mat.
There are some vegetables that you might want to start indoors because when they’re started outdoors, their chances of survival are low since the transplant shock is too much for them. You might want to start these starter plants indoors:
-Celery (It may not survive outdoors after it’s started indoors.)
-Leek (don’t like being transplanted once they’re established)
-Onion starter plants (onion is usually planted in starter plants)
Here are some vegetables you can plant directly outside because there’s little or no transplant shock associated with growing the vegetable seeds outdoors:
-Beets
-Carrots
-Corn (Husk the first few ears of corn that come off of each seedling plant; ear size determines how big your mature corn plants will be.)
-Endive (Belgian endive needs 2 months of cold to form curds)
-Escarole (Belgian endive needs 2 months of cold to form curds)
-Kale
-Lettuce, all types
-Onions (onion starter plants)
-Parsley (flat-leaf parsley is ready in 8 weeks; Italian parsley is ready in 12 weeks)
-Radish starter plants
-Scallions (green onions)
How to Sow Seeds Indoors: How to Start Seeds Inside?
The sow seeds indoors process is easy. You just need starter soil or starter cells on a seedling mat and seeds. If you’re unfamiliar with sowing seeds indoors, read below for more information about how to start vegetable seeds inside.
All you have to do is choose starter soil from a list of starter soils, sprinkle the seeds onto the starter soil, water them in, and keep them warm. The warmth part is important because different vegetable seeds have their own germination requirements. This means that some seeds need a certain temperature to sprout and grow—between 70 degrees F and 85 degrees F for most vegetables—while others need much colder temperatures so they don’t sprout over winter or die after they’ve germinated. These cold-germinating seeds include Beet, Carrot, Corn, and many others.
Types of Seed Containers
Seed starter pots or starter cells on a seedling mat should be used for most vegetable seeds. These pots are the same size as the starter cups that are used in starter plants. The starter cells are small starter pots that are made out of paper.
A starter pot is a container that has starter soil in it, making it perfect for sowing starter plants indoors. Starter cells are pots made out of paper or cardboard. They hold starter soil and can be used either inside or outside by inserting them into the ground.
If you have starter plants, you can plant them in starter cups or starter pots. However, if you have starter plants that are already outside and seedlings that are still inside, then use starter soil on a seedling mat to hold your seeds until they germinate.
The starter soil is the same thing as a potting mix—anything that holds water but that also has nutrients to feed your vegetable plants. It’s moistened with fertilizer for growing vegetables indoors.
-Plastic starter pots (soil drain off pretty quickly)
-Cardboard starter cells (good starter container for starting seeds reliably; comes with perforated growing cells)
-Cell packs (consist of six 10″ x 20″ sheets of paper starter pots)
-Ceramic starter pots (some starter pots are made of plastic or porcelain)
Starter Soil for Vegetable Seeds
2/3 starter soil 1/3 compost is the mix to use for starter cells, starter cups, starter containers, and starter trays. If you have your own garden mix that’s looser than what you normally use in their garden, then use at least half potting soil or planting mix for sowing seeds indoors.
Ideal Time for Starter Seeds
You should start these vegetables indoors after all danger of frost has passed. Some can be sown as early as February, while others are best started in April. Here are all the starter seeds you should start indoors, including their ideal time for sowing starter plants indoors.
-Beets (February to March)
-Carrots (April)
-Corn (April)
-Endive (Belgian endive needs 2 months of cold to form curds; sow mid-March to early May)
-Escarole (Belgian endive needs 2 months of cold to form curds; sow mid-March to early May)
-Kale (March – April is best for most types of kale; 6 weeks before your last frost date will be best for Dwarf Blue Curled Scotch and Dwarf Green Curled Scotch; also known as “Greens”)
-Lettuce (February to June; sow anytime; for head lettuce, wait until March or April)
-Lima beans (March – frost won’t hurt them)
-Okra (April)
-Onions (set out starter plants as early as possible—before your last frost date is ideal; if you’re planting from seeds, then plant mid-March; should be sown indoors in starter cells and transplanted outside after all danger of frost has passed)
-Peas (should be sown indoors in starter cells and transplanted outside after all danger of frost has passed. They can also be planted from seed outdoors once the soil temperature reaches 65 degrees F.)
-Peppers, Hot/Sweet Bell Pepper hybrids (April)
-Potatoes (March – April)
-Pumpkin (April – frost won’t hurt them)
-Radishes (must be sown indoors in starter cells and transplanted outside after all danger of frost has passed. They can also be planted from seed outdoors once the soil temperature reaches 40 degrees F.)
-Spinach (February to March)
From Starter Seeds to a Garden in 4 Steps
Get your starter soil and starter seeds together. Sow the starter seeds indoors in starter cells, starter cups, starter pots, and starter trays. Gradually expose your starter plants to outdoor conditions (grow lights may be necessary during hot summer days).
As soon as you can tell that your starter seeds have germinated, transplant them into larger pots or into the ground outdoors. Vegetable seedlings should be transplanted outdoors once they are about 4 inches tall. If you are growing vegetables from heirloom or open-pollinated seeds, then try to get at least 6 true leaves for cabbages before transplanting outside.
- Read this article about how to start seeds inside , so that you know which ones will work best for you to get your starter seeds started.
- And this article about vegetables that grow best from starter seeds indoors .
- By growing starter seeds inside, you get a head start on the rest of the garden. You’ll need less time between setting out transplants and harvesting crops. It’s also less expensive than buying starter plants or transplanting seedlings outside. And it saves you having to buy starter soil because you can recycle your own planting mix to use as starter soil for vegetable seeds indoors. This recycling idea is especially good if you are planning on starting lots of starter plants indoors, like all those tomato plants that are needed for an abundant summer garden!
- Start these vegetables indoors after all danger of frost has passed. Some can be sown as early as February, while others are best started in April.
Get Started With Starter Seeds Today
You can save time and money by starting starter seeds indoors. This article has all the starter seed planting basics you need to know, including how much starter soil is needed for starter plants, what type of starter pots are best for different types of vegetables, when your starter plants should be transplanted outside, and more! We’ve also included links to articles with info about specific vegetable starters that grow well from seeds started inside.
FAQ
What does Seed Starter mean?
-Seed starter is the term given to starter plants grown indoors for transplanting outside.
How should I plant starter seeds inside?
-You can use starter cells, starter cups, starter pots or starter trays to start your indoor seedlings. Garden soil, vermiculite and perlite are all used as starter soil for vegetable seedlings started indoors. Transplant them into larger pots (also known as 4″ square) when they’re about four inches tall; if you’re growing vegetables from heirloom or open-pollinated seeds, try to get at least six true leaves before you set them outside.
Is it OK to start seeds in potting soil?
-It’s usually preferable to start vegetable starter seedlings in starter soil mix, but gardeners often recycle their own potting soil when starting starter seeds indoors. Usually this is because they are planning on starting lots of starter plants indoors – for example, all those tomato plants that are needed for an abundant summer garden! But starter cells, starter cups, starter pots and starter trays work fine for sowing most types of vegetable seeds.
Can you put seeds straight into the soil?
Some starter seeds can be sown directly into the soil, such as peas and beans. But if you don’t know which starter seeds to start indoors, then use starter cells (individual peat pots), starter cups (paper or plastic cups for one plant), starter pots or starter trays instead.