50+ Seeds To Start Indoors In April
April is here and as gardeners we’re likely all saying “I’m behind on seed starting!” Right? There’s so much to do, so much to seed. But take a deep breath and slow down. You don’t need to do it all. So pick and choose what seeds to start, and most importantly — enjoy the process! This post will walk you through 50+ seeds to start indoors in April.
If you’re a gardener across the Canadian Prairies, we’re now about 6-8 weeks from our last frost date. Finally!
If you’re located in warmer Canadian grow zones, like on the coasts, your last frost date might be much closer. Or have already passed! If that’s the case — you would have/should have already started most of these seeds back in March.
All that to say, this post is intended for gardeners living in Zone 2-5 as listed in Canada’s Plant Hardiness Zone Map.
To find the exact last frost date for your area, try out my fav tool, The Farmer’s Almanac Local Frost Finder.
Enter your postal code/zip code and it will pull up fairly accurate info related to average frost dates.
Once you know your last frost date, you can dig into this post with a clear understanding of when exactly to start these seeds in the month of April!
50+ Seeds To Start Indoors In April
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As there’s SO MANY seeds to start indoors in April, I’ve split this post up into three categories:
Select any of the categories above to be pulled directly to that section of the post.
And remember, you don’t need to start everything I’ve listed here. In fact, you won’t have much fun with your garden if you try to do so.
Start with the seeds you like to eat and enjoy the most. Then every year moving forward, add a few more to your seed starting!
Plus, don’t forget — you don’t even need to start any seeds indoors to grow an amazing, organic food garden. You can simply wait until your last frost date and direct sow a variety of seeds then.
Gardening should be fun! So do what best fits your lifestyle.
P.S. You can still start any of the seeds listed in my post 20 Seeds To Start Indoors In March In The Canadian Prairies, just know that you’ll have a later harvest.
15 Veggies To Start Indoors In April
Ordered from earliest seeds to start in April to latest.
Kohlrabi is best started anywhere from 10-6 weeks before your last frost date. It’s an unusual looking root vegetable in the brassica family.
I personally don’t grow Kohlrabi anymore in our garden because we don’t eat enough of it. But it is easy-to-grow and definitely an eye-catcher. It’s like an alien veggie the first time you see it!
Fennel does best when started indoors about 8 weeks before your last frost date, but even a few weeks earlier than that works well too.
Wait until well after your last frost date to transplant fennel into the garden.
Chicory/Radicchio is one of my all time fav veggies to grow in the garden simply because it is so beautiful and really brightens up a salad. Plus there’s so many varieties to choose from. I suggest starting your seeds in the first week or so of April. Or about 7-8 weeks before your last frost date.
Try Radicchio di Lusia for a beautifully, speckled head of leaves.
I like to start them indoors at the beginning of April, about 7 weeks before my last frost date, and then transplant in the garden a few weeks before my last frost date. Asian Greens are cold-tolerant and don’t mind a bit of frost.
Scallions are easy-to-grow and do best when started about 6 weeks before your last frost date. For my Zone 3 garden that’s about mid-April.
There’s so many fantastic Scallion varieties to choose from too! I’m growing these Red Beard Scallions this season for the first time. The red roots will look really pretty in a salad or as garnish on a dish.
Rapini/Brocolini is a quick maturing style of broccoli that produces small leaves, stems and buds. I start mine indoors in early April, about 7-6 weeks before my last frost date, and also transplant it in the garden a few weeks before my last frost.
I particularly love the variety, Zamboni that is ready to harvest in just 45 days.
You may be surprised to see romaine listed as a veggie to start indoors in April. You can certainly direct sow your Romaine Lettuce seeds in the garden when the soil is workable. But because the seeds are so fine and delicate, I like starting them indoors 4-5 weeks before my last frost date. I then transplant them out by about mid-May, a few weeks before my last frost date.
Swiss Chard is another veggie that could easily be direct sow’d in the garden. But I find starting the seeds indoors within the first 1-2 weeks of April (5-4 weeks before my last frost date) gives me a head start on my harvest.
Try the variety, Celebration for a mix of multicoloured chard.
Collards produce big, wide bunches of green leaves that have a rich, savoury flavour. I suggest starting collards indoors 4-6 weeks before your last frost date. However, you can transplant them out in the garden before the risk of frost is gone as they are pretty cold-tolerant.
You might be surprised to hear that we CAN in fact grow Sesame Seeds in a Zone 3 garden! It’s true and actually a relatively easy plant to grow.
Start your sesame seeds indoors 4-6 weeks before your last frost date. They require approx. 90-110 days to mature, so expect to harvest by late Summer, early Fall. I grew Sesame for the first time last year and waited until the stalks were dried before harvesting.
Wait until the end of April to start your Summer Squash/Zucchini seeds. I find waiting as close to your last frost date as possible before starting results in stronger seedlings. They tend to get stressed if indoors for too long. So wait until about 4 weeks before your last frost date to start your Summer Squash/Zucchini.
Wait until the end of April to start your Winter Squash seeds. This includes everything from Butternut Squash, Spaghetti, Hubbard and more.
I find waiting as close to your last frost date as possible before starting results in stronger seedlings. They tend to get stressed if indoors for too long. So wait until about 4 weeks before your last frost date to start your Winter Squash.
Similar to Summer and Winter Squash, Pumpkins do best when transplanted into the garden shortly after started indoors. So also wait until 4 weeks or less before your last frost date to start them.
This year, we’re growing this gorgeous French heirloom pumpkin, Rouge Vif d’Etampes that I’m so excited about!
Start your Melon seeds indoors anywhere from 4-2 weeks before your last frost date. Melons are tender vegetables and shouldn’t be transplanted outside in the garden until there’s no chance of frost. I usually wait until the first week of June to transplant our melons in my Zone 3 garden.
Cucumbers can either be direct sow’d in the garden for a later harvest, or started indoors for an earlier harvest by early summer.
I prefer starting our cucumbers indoors about 2-4 weeks before our last frost date. Be sure to wait until any chance of frost is gone before transplanting in the garden. If you have a greenhouse, you can transplant you cucumbers in there much earlier. Cucumbers are heat-loving veggies and do really well grown in grenhouse settings.
20 Flowers To Start Indoors In April
This list is is not arranged in any specific order, all flower seeds should be started as early in April as possible. Or no later than 5-6 weeks before your last frost date.
Hollyhocks give a garden that cottage-chic vibe that is super on trend for 2022. They’re such a pretty flower!
I actually like starting my Hollyhocks at the 8 week mark before my last frost date as it results in blooms earlier in the season.
I know many gardens who choose to direct sow their Zinnias instead of starting indoors. I personally like to do both, which allows me to have blooms throughout more of the season.
Nasturtiums can be either direct sow’d in the garden or started indoors. I suggest starting them indoors as they transplant really well and make laying out garden beds easier.
You can either buy compact varieties of Nasturtiums or ones that grow great, big vines and foliage. The latter is my fav! They are beautiful spilling down the side of a raised bed or crawling up a trellis.
I discovered Amaranth last season and fell in love with them as a cut flower. They add a really unique look to bouquets and make great filler. Start you Amaranth indoors 8-6 weeks before your last frost date. For me, that’s usually the end of March or beginning of April.
Transplant in the garden after the risk of frost is gone. I love the variety, Green Tails Amaranth! They have long, drooping tassels.
Dianthus is a bit of a challenging flower to grow. The seeds are very fine and can be difficult to germinate. However, it is hardy as an annual up to Zone 3, which does make it worth the challenge in my opinion.
You can start your Dianthus seeds indoors as early as 10 weeks before your last frost date.
My Mexican Torch Tithonia is the flower I think I’m most excited to grow this season! It gets towering tall, standing up to 8ft!
I started my seeds the first week of April and will wait until well after our last frost (likely the first week of June) to transplant into the garden. I’d suggest starting yours anywhere from 8-6 weeks before your last frost date.
Lupins are another stunning flower that work well as a border plant along a pathway and add a whimsical, fairy-garden vibe to a garden.
I find Lupins can be started indoors as early as 10 weeks before your last frost date, but in past years I’ve waited until mid-April (about 5 weeks before my last frost) to start them and still enjoyed beautiful blooms.
African Violets are dainty, compact flowers that are perennials up to Zone 5.
They can be moderately difficult to grow as the seeds are super tiny. Germination can also be slow, so start them as early in April as possible.
There’s several really pretty Alyssum varieties to choose from, including my fav yellow variety, Basket of Gold.
Alyssum can be started as eary as 10 weeks before your last frost date.
Cornflowers or Bachelor Buttons are really easy to grow and pretty low maintenance. A great flower for beginner gardeners! My first year growing them, I neglected them as we were busy planning a wedding and they still produced tons of purple and pink flowers all season long.
You can also direct sow cornflowers after your last frost date. But if starting indoors, start 6-4 weeks before your last frost date.
Calendula will forever be one of my fav annual flowers because of its many uses. I use it for bouquets, the petals in salads and dry the heads to infuse into body oil.
Start your seed indoors 6-4 weeks before your last frost date. I’ve actually had the best luck when germinating calendula seeds in dark. I simply place a tray overtop of my seeds. Once germination occurs, I move them under bright lights.
Delphiniums do best when started as early as possible. I suggest starting them as early as 10 weeks before your last frost date. You can wait until 6 weeks though.
A gorgeous purple variety is Rocket Larkspur.
Campanula flowers produce tiny bell shaped flowers that work really well as a cut flower.
Start them indoors anywhere from 10-8 weeks before your last frost date. The seeds are very tiny so barely cover with soil when germinating.
Cerinthe flowers are a great annual flowers for beginner gardeners. They do well in both sun and shade gardens and produce really unique looking blooms.
You can start them as late as 5-6 weeks before your last frost date.
Gaillardias look like a mix between Echinacea and Daisies. They’re beautiful and become quite bushy, taking up lots of room in the garden. Start them indoors 6 weeks before your last frost date.
Iberis can either be direct sow’d or started indoors 6-8 weeks before your last frost date. Some gardeners say they can be difficult to transplant, but I’ve never had an issue!
Iberis flowers will produce blooms all season long, such a win.
Lavatera flowers are a great addition in cut flower bouquets and produce both great foliage and tons of flowers.
Start them indoors anywhere from 6-8 weeks before your last frost date.
We’ve all seed the trendy Pampas Grasses in vases and on Instagram. And April is the right time to start them and other Ornamental Grass seeds indoors.
Start them as early as 10 weeks before your last frost date. Then transplant in the garden after any risk of frost is gone.
Scabiosa or Pincushion Flower produce really beautiful double blooms. I’ve started them as late as the last week of April (only about 4 weeks before my last frost date) and they still produced blooms by mid July. They’re a pretty easy-going flower, perfect for beginner gardeners.
Veronica flowers are similar in appearance to Lupins, but are actually hardy as a perennial up to Zone 3. Great news for us cold climate gardeners!
Start them indoors anywhere from 10-6 weeks before your last frost date.
15 Herbs To Start Indoors In April
List is arranged in alphabetical order, all herbs can be started at any point throughout the month of April.
Agastache is a cold tolerant perennial herb hardy to Zone 4. It is extremely fragrant and almost has a licorice-like smell to it. Super cool!
Start seeds indoors as early in April as possible. The seeds are very fine, so barely sow them below the soil’s surface.
Arnica is an easy-to-grow perennial with some varieties that are even hardy to Zone 3. It’s on my list to grow this season! I plan to start my seeds by mid-April (about 5 weeks before my last frost date).
The bright, yellow flowers add a pop of colour to the garden, but Arnica also has medicinal properties when used in topical products.
You may have heard of Ashwagandha as the “superfood” stress adaptogen. It’s a deeply medicinal plant and both the roots and leaves can be harvested.
It’s suggested ashwagandha is started indoors at least 4 weeks before your last frost date. So depending on your grow zone, start it at some point within the month of April.
The great thing about growing Basil is that it is really fast growing, so can easily be started at any point in April or as late as May…even June!
Wild Bergamot or Bee Balm as it is commonly called, is a really unique looking flower that can be used in teas or as a garnish in dishes. It will attract many pollinators to your garden too, which is always a plus!
I like to start my Bergamot seeds 10-8 weeks before my last frost date. The first week of April is ideal. The seeds are very fine and tiny, so barely cover with soil when seeding.
Many gardeners prefer to direct sow Borage as oppose to starting indoors because the roots can be easily disturbed. However, I enjoy starting it inside and have never had any issues when transplanting.
Start Borage seeds 6-8 weeks before your last frost date. The bees will thank you for planting it!
Catnip is a herb that isn’t only attractive to cats (lol)! It actually produces really pretty flowers that work well in arrangements and also dry nicely.
Start your Catnip indoors 6-8 weeks before your last frost date. You can also direct sow it in the garden for a later harvest.
Epazote is a really fun, unusual herb that is big in Mexican cooking. It’s said to help with indigestion and I know many gardeners who use it in teas.
Start your Epazote seeds indoors 6-8 weeks before your last frost date. Be patient as germination can take up to two weeks.
If you’re going to grow any unusual herb this season, make it Indigo! Like its name implies, the leaves have a blue dye in them that can be used to turn fabric blue. Natural dying seems like the next big thing and how fun to really embrace the “slow fashion” concept by growing Indigo and dyeing old clothing.
Indigo seeds should be started 4 weeks before your last frost date. The seeds are small and barely need to be covered with soil.
Parsley is a herb that can be started indoors or direct sow’d. It’s up to you! The benefit with starting inside is that you’ll be able to enjoy a harvest much earlier in the season. Plus, parsley is a cool-season herb and can be transplanted in the garden before your last frost date. Just be sure to harden it off properly first.
Lemon Balm is an easy-to-grow annual herb that can be overwintered as a perennial in Zone 5 or warmer. Start your seeds 6-8 weeks before your last frost date. Then wait until after your last frost date or until temps are consistently above 10°C/50°F to transplant outside.
Lovage is a really flavourful herb that has a bitter yet salty flavour, almost like celery. It’s very easy to grow but can get quite large in the garden, so be sure to give it lots of room to spread out. It is a perennial in Zone 4 or warmer, so also be sure to plant it somewhere in the garden where you can easily protect it over Winter.
Start your Lovage indoors anywhere from 6-3 weeks before your last frost date.
Marjoram is a Mediterranean herb often called Za-atar. The leaves are really flavourful and work well infused in oils and vinegars or dried.
Marjoram seeds are very fine, almost dust-like! So I find starting them indoors is much easier than direct sowing as you have more control of their growing environment. Start them as early as 10-8 weeks before your last frost date.
Summer Savory is the new hot herb, in my opinion! It’s super aromatic and releases a strong scent even when you just walk by it in the garden. I personally love it mixed into salads.
I start my Summer Savory mid-April, about 5 weeks before our last frost date. The seeds are delicate so I sow several per cell and then separate once I’m potting up.
You might be surprised to see Tobacco on this list, but it’s an easy-to-grow and beautiful herb that can get really tall even in a Zone 3 garden. Our plants have gotten to 5ft in past seasons!
Start your Tobacco seeds indoors at the start of April, or 6-4 weeks before your last frost date. Transplant after your last frost.
And there you have it!
You now know about 50+ seeds you can start indoors in April! Take it slow and steady. Start only a few things and grow your garden every year following.
I wish you all the best in your April seed starting.
If you have any unanswered questions, be sure to comment below. I love hearing from you and answer all comments.