If you are starting a garden then try these easy to grow annual flowers from seeds that will be blooming all summer long with minimal care in full sun or partial shade.
If you are fine reading my short story, I garden since I was little in grade school, growing up in a tropical country and grow the garden all year long. Then I built the little veggie garden patch beside my parent house.
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I planted onion, garlic, tomatoes I got from my mom’s kitchen scraps. Both my parents are gardeners in our big family, so I learned a lot from them.
Because we have tropical weather, so lots of flowers are perennial there including the easiest marigold one.
Now, since I move to four season country and garden in zone 4A to be exact, finding flowers that will fill up the garden space quickly is my priority every year.
Gardening in Zone 4A is very challenging, include short growing season or unexpected weather conditions.
So, here are 15 easy to grow annual flowers that will bloom all summer long. All annual flowers on these lists are easy to grow from seed, whether it is direct sow or start early indoors.
Annual Flower For Full Sun
This sweet honey fragrant flower is blooming from spring to frost. You can do indoor seeding before last frost or direct sow outside.
There is a seed company that carries sweet alyssum seed on paper tape, make it easier to direct sow outdoors. This plant has a small dainty flower that is great for edging, border, or filler between plant to help reduce weed grow freely. It comes with some color varieties, purple, white, lavender and rose.
Baby Blue Eyes
This plant has a bright blue flower just like the name, and it grows about 6-10 inches tall make it perfect for edging. You need to start the baby blue eyes seed indoors about 4-6 weeks before the last frost or direct sow after the last frost.
The top choice for cut flower and surprisingly it is straightforward to grow from seed. I did indoor seeding and direct sow, and both are growing at the same rate and blooming all summer long.
This flower often called marigold. Both are the Asteraceae family, but it has different leaves and blooms. Calendula is one of the quick plants to grow from seed, and quickly from direct sowing.
Calendula is a cold hardy annual and frost tolerant plant that will self-seed freely. Calendula is one of the best tomato companion plants.
This flower has a daisy-like flower and comes with varieties of colors, pink, white, red, purple, bi-colors. Some types grow up to 4 feet and need staking. Cosmos is one of easy annual flower for direct sow outside.
You can plant it indoors about four weeks before the last frost for early blooming. Cosmos often self sow freely, and it is one of the cold tolerant plants.
This annual plant has feathery and comb-like flowers. Celosia is heat and drought tolerant and will die out when frost is coming.
It is better to sow the seed indoors before the danger of the last spring frost. The feathery flower is excellent for cut flower.
The flower and foliage are edible that has a slightly peppery taste make it an excellent addition for salad. Plant the seed 4-6 weeks indoors before the last frost, or direct sow outside once the soil warms up in the early spring.
Nasturtium has a hard shell coating, and it is recommended to soak the seed first before planting. Keep in mind though, nasturtium will grow in poor but well-drained soil, and the plant grows fast so it can take over the planting area quickly.
There is French marigold and African marigold, and both types are beautiful. You can plant it from seed indoors or direct seeding.
Marigold is perennial for a tropical region, and it is annual for the colder zone. Even though it is annual for the colder area, but it often self sow freely, so I always find new marigold seedlings around original plants from the previous year.
Then I will move these seedlings all over the garden as it is a warrior flower to reduce nematode in the soil and it is one of the top choices for companion planting with tomatoes. Marigold is a fast-growing annual flower from seed, so it always my top pick to grow every year.
The long stalk flower is excellent for cut flower and dried one. Sow the seed indoors 6-8 weeks before the last spring frost or direct sow after the last frost date. Statice flower color comes in blue, pink, mauve, red, yellow and the color stay the same when it turns into a dried flower.
There is two different stock, Night Scented Stock (Matthiola Bicornis) and Ten-Week Stock (Matthiola Incana). Both varieties are very sweet fragrant, and the night-scented stock flower has a strong scent in the evening.
Start the seed indoors about 6-8 weeks before the last frost. You can also direct sow outside after last frost date.
It is probably the most favorite flowers to grow among kids as it is easy to plant and produce big blooms. Some varieties are short, and the tall varieties will need staking. Some blooms produce edible seeds, and some blooms are a perfect addition for cut flower.
Sunflower needs full sun and warm weather to grow, and it is better to direct sow after the danger of the last frost. It might need a long warm summer to grow into the fullest, but I found that the shorter variety will bloom all summer long.
There is also a perennial false sunflower that looks similar in appearance with smaller daisy-like blooms.
The flowers come in varieties of colors, single or double blooms. The long flower stalk makes it a perfect addition for cut flower.
You can sow the seed indoors a few weeks before the last frost, but I find it direct seed outdoors after the last frost make the plant grow better.
Zinnia likes hot, dry areas and it dislikes wet soggy soil. The blooms are showy, perfect for mass planting.
Annual Flowers For Partial Shade
This fragrant flower is not the edible version of peas. Sweet peas plant is an annual vine and a cold hardy plant.
Although, it is one of the annual flowers for full sun, it always a good idea to grow it in partial shade to extend the bloom. Direct sow sweet pea seeds as soon as the soil warms up and workable, usually in the early spring after the hard frost.
Although snapdragon grows best in full sun, it also tolerates some afternoon shade. I would start the seed indoors 6-8 weeks before the last spring frost.
Snapdragon is a tender perennial, frost tolerant but treat it as an annual in a colder zone. The long cluster flower spike is excellent for cut flower and good for edging. Cut the spent flowers to encourage more blooms.
This flower is the most famous option for a container garden. Although it is easy to grow from seed, it requires indoor seeding about three months before the last frost.
So, the last frost date in my area is between May 21-23, and I would start sowing petunia seed indoor around February 15, which is a long time to plant sitting before it ready for their final spot outside.
Some varieties tolerate a light frost, and it comes with single or double blooms. Some petunia varieties also have fragrant flowers, upright and spreading habit. It grows best in full sun area, but it also tolerates some shade.Plant these easy to grow annual flowers from seed that will bloom all summer long #gardeningtips #flowergarden #gardening Click To Tweet
While some of these annual flowers seeds can be direct sow outdoor, but keep in mind if you live in a four season and colder zone, then you should direct seeding after the danger of the last frost.
Otherwise, most of these flowers will die out because these are tender plants. If you plant these flowers from the seed package, always read the plant instructions listed on the label.
Also, check with your region where you live to make sure if these plants are not on the list of invasive plants.
How To Harden Off Indoor Started Annual Flowers
You need to harden off indoor started annual flowers or any plants before they are ready for their spot outside to prevent shock such as wilted, dried out or worse died out, not fun I know.
This process is as simple as gradually expose these plants into the outside environment for a few hours and bring it back inside about two weeks before the last frost date in your area.
You have to increase more hours every day for about two weeks started in the protected shade area like a patio. Then gradually expose it into the sunlight, wind, or rain then bring it back indoor until it ready to be left alone outside for the whole day and night.
If there is frost in the forecast, then withhold the hardening off process. These plants are usually ready for their final spot outside after the hardening off process finish.
What Is The Soil Condition For Growing Annual Flowers
As many other plants, such as flowers, vegetables, shrub or trees except bog tolerate plants, needs well-drained soil with lots of organic matter. Some annuals grow well in a sandy area like those for the rock garden, but it still needs to be well drained.
If you have clay compacted soil, add more organic matter like compost, peat moss, worm casting, or well-composted manure when you work on turning that soil so you will get a suitable growing medium.
I have a clay soil all over the garden, so I would mix in these organic matters with perlite and keep adding more compost or manure every spring for soil amendment.
If you have a small garden, or just building a raised garden box, you can use the premix garden soil. If you use the topsoil package, you have to mix it with compost or manure again before planting.
Some annual flowers or any plants also grow on certain ph balance on the soil. You can test the soil with pH starter kit if you are unsure about it.
How To Water Annual Flowers
Just like many plants, you don’t need to water them until it gets waterlogged. If the plants are outside in the garden already, it always best to water them in the morning, so it has a chance to dry out or evaporate before the night comes to prevent plant disease like fungus or blight.
If it grows on the container, make sure the soil doesn’t dry out. If it rain comes, then you are lucky you don’t need to water them.
But all annual flowers I mentioned here are not difficult to grow and no picky about watering system either.
DIY garden projects you can do this year.
Even though some of these annual flowers are frost tolerant, it always a good idea to cover them with blanket frost or cloche. Some tender seedlings or mature plants might not be strong enough to handle frost that coming suddenly.