6 Vegetables That We Always Start Indoors

January in Iowa. Yes it’s cold. Yes there is snow on the ground. Yes the wind is blowing so hard it feels like it will bite through your clothes and right into your soul.

April can feel so far away this time of year, but January is an important month for us still. This is when much of the garden planning, seed ordering and initial prep work for our garden season begins.

We’ll be starting our seeds indoors in the next month. Transplants are an important part of our planting scheme. Many of our crops are grown from putting seed right in the ground, but there are certain crops that we always start indoors in order to transplant them when the ground is warmer.

Why transplant? Many crops can be started indoors under grow lights rather than by direct seeding. The advantages to this include stronger disease resistance, protection against late frost or other weather events and protection against birds or other animals that like to dig up seed. It’s also a great way to get a jump on long maturity dates.

Not to mention that it’s fun to start seeds indoors when there is snow on the ground.

Certain plants should always be started indoors, in my opinion. Here are six vegetables that you’ll have higher success growing if you transplant rather than direct seeding in the garden.


Tomatoes can be fickle when they are first starting out. They’re not hard to grow, but you’ll often have variable results if you try direct seeding them outdoors.

In order for tomato seeds to germinate, your soil temperature needs to be around 70 degrees. They’ll need a steady source of light until they sprout, which means you don’t want to plant them too deep. We plant ours about 1/4 inch and lightly cover with soil. The soil should be kept moist, but not saturated or the seed can rot. Once your seeds sprout and start to grow you’ll want to keep them under direct light for at least 8 hours a day.

Start your seeds no later than 4-6 weeks before the last frost in your area. We start ours around 8 weeks before last frost because I like to have a little more stem height when I transplant. This allows me to bury the stem nice and deep to ensure strong root development.


Peppers are part of the Solanaceae (Nightshade) family, just like their cousin the tomato. They aren’t difficult to start from seed but getting consistent germination can be frustrating with certain varieties.

We plant our pepper seeds just like we do our tomatoes, but we’ll start them at least 8-10 weeks before the last frost as they take longer to grow. Some varieties, including hot peppers like habanaro and ghost, should be started a week or two earlier.

The trick to germinating peppers is consistent moisture and soil temps around 70-80 degrees. I’ve found that sometimes an overhead light isn’t enough to get good germination. We start our seeds in Jiffy Peat Pellets underneath a clear plastic cover, which creates a kind of extra greenhouse effect under the lights, trapping in the moisture and heat. Usually, if your growing room is warm enough, there is no need to use a heat pad. Once the seeds sprout, we remove the plastic cover and expose the seedlings to 8 hours of light each day. Usually ambient daylight coming through the window will be good enough.


We start our broccoli indoors around 7 weeks before the average last frost date. In some climates, broccoli can be direct seeded, but we’ve found that our broccoli is much more healthy and better developed when we transplant. Flea beetles love to eat young broccoli seedlings as they emerge, often decimating a whole crop overnight. Deer like to munch on broccoli too. Transplanting can give your young broccoli plants a better opportunity to grow strong enough to survive these common pests.

Broccoli will germinate in soil temps as low as 45 degrees, and will usually only take 4-7 days. Broccoli thrives in cooler weather, but make sure temps are consistently above 55 before you transplant or else you might have early bolting (your broccoli head flowering and going to seed).

Cabbage & Cauliflower

Cabbage and cauliflower are handled the same way as we do broccoli. All three are part of the same family and have similar growing traits.


Celery is a tiny seed that takes up to 3 weeks to germinate, which makes it a good candidate for starting indoors. We’ll start our celery around 12 weeks before the last frost, under LED lights. Room temperature should be around 70 degrees. Moisture should be even but not overdone.

When transplanting, makes sure outdoor temps are consistently above 55 degrees. Celery can withstand light frost, but too many cool nights and temps below 55 will cause early bolting.

Celery takes a long time to mature, so starting with strong, healthy plants is essential. It does well in the high heat of summer here in Iowa, as long as we keep the soil moist, and we will usually start to harvest in August. That’s a long journey from seed to table!

    1. Not this year, but I can point you to where we get our seeds. Check out Johnny’s online or Baker Creek Heirlooms.

  1. I wish I could do this but literally have no room indoors. I have to buy already started plants. Maybe someday I will have a greenhouse.

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