How to Grow Annual Plants: 7 Tips for Caring for Annuals

Annuals are plants that complete the entire life cycle in one growing season. Unlike perennial plants—which grow year after year—annual crops germinate, grow, harvest, and die within the course of a year, and you need to replant them the following year.

Some annuals drop seeds organically, meaning they can grow the following year without physically re-seeding. Annuals that self-sow include cosmos, candytufts, California poppies, and larkspurs.

Annuals fall into three main categories: tender (summer), hardy (winter), and half-hardy annuals. These classifications determine a plant’s ability to withstand frost and colder temperatures.

1. 1. Tender annuals: Considered warm-weather crops, tender annuals have little to no tolerance to freezing temperatures. You should plant tender annuals a few weeks after the final frost. Examples of tender annuals include basil, eggplant, cilantro, dill, marigolds, and angelonias (which are tender perennials in some areas).
2. 2. Hardy annuals: These plants are most tolerant to cold weather and frost, and you can sow them in early spring. If you choose to start earlier, grow hardy annuals indoors and transplant the seedlings once your garden soil is workable in the spring. Examples of hardy annuals include broccoli, snapdragon, viola, and larkspur.
3. 3. Semi-hardy annuals: These plants can withstand some colder temperatures, but they aren’t as tolerant as hardy annuals. You can plant half-hardy plants a few weeks following the last hard frost. Half-hardy plants include cauliflower, pansies, geraniums, petunias, and baby’s breath.

With annuals, you can start from seeds, seedlings, or developing plants—all of which you can find at a garden center or online. Each option has its advantages and disadvantages depending on your time and skill level:

• From seeds: While a cost-effective way to start gardening, seeds take the most time to develop into adult plants. If you’re looking for a rare plant, you may need to start from seeds.
• From transplants: Using transplants is the easiest and quickest way to garden. Transplants develop much quicker than seeds, though it is likely more costly and you give up some control over the plant’s growth. If using transplants, dig a hole big enough to fit the root ball.
• From seedlings: Transplanting seedlings, or very young plants, into your garden is a mixture of both options. Plant seeds indoors under a grow lamp or with access to lots of natural sunlight. Once the seeds begin to sprout, uproot the plant carefully, and place it in your outdoor garden. Leave the root ball undisturbed.

When first planting annuals, ensure your seeds or transplants’ root systems have enough room to grow, typically between 1–3 feet of space between each row. You should plant winter annuals in later autumn or early winter if starting from seeds. They will continue to germinate through the winter and will bloom come spring. You should plant hardy winter annual transplants in the early spring for bloom in winter.

While some plants grow as annuals, they may not fall under the category of annuals. Some flowers and vegetables—black-eyed Susans, onions, pansies, tomatoes, geraniums, tulips, impatiens, and more—are short-lived perennials grown as annuals. You can grow perennials as yearly plants, but you cannot grow annuals as perennials.

Once you have planted your annuals begins the process of caring for them. Here are a few tips to properly care for your budding annuals:

1. 1. Find your plant hardiness zone. The United States Department of Agriculture (USDA) maintains an online hardiness map, searchable by zip code, which divides the country into 13 zones based on average annual minimum temperature. The map also features a zone finder to locate the zone you live in. Find your zone and familiarize yourself with the fruits, vegetables, flowers, and herbs that thrive there.
2. 2. Water well and check in. You need to water all perennial garden plants so they can grow. Add about one inch of water, depending on the soil moisture. If it feels too dry, add an extra inch of water. When the weather is cooler in early spring, water your annuals about once a week, increasing to two or even three times per week once the air temperature increases.
3. 3. Compost and mulch your soil. Composting is popular for the many benefits it brings to vegetation and the environment. The organic and biological materials living in compost activate the soil's contents, which include fungi, bacteria, minerals, among others. This promotes strong immunity in your plants, and expands the life of your crops. Adding mulch, organic fertilizer, or other organic matter to the top layer of your soil can also give your vegetables a head start in growth.
4. 4. Use a natural or organic pesticide. Vegetables are prone to pests like flea beetles and aphids. For bugs, use an organic or noninvasive pesticide. You can also make your own natural pesticide at with a few ingredients. To keep critters or larger animals from getting into your crops, net and/or fence the perimeter of your garden.
5. 5. Weed often. Weeding prevents fungus or disease from infecting your plants and is an essential step for proper plant maintenance. Include weeding in your everyday gardening routine. You'll want to do this in the morning when the soil is damp, and you can easily remove the weeds.
6. 6. Prune and deadhead thoroughly. As your plants begin to bloom, you should prune your garden to remove any dead or dying foliage. Additionally, you can remove spent flowers and prevent smaller corps by deadheading, pinching, or cutting off dead blooms and young bugs. For vegetables, remove dead leaves or stems. This will ultimately improve the look of your garden over time while also promoting healthy, new growth.
7. 7. Start a diary. Keep a garden journal to track your veggies' progress. Keep notes of when and where you planted your vegetables, if pests or critters are interfering, or any pertinent details to the development or health of your crops. Be as detailed as possible and log information on a daily basis. Starting a garden is an investment of time and labor, and the best way to reap those rewards is through daily logs.

True annuals do not live for more than one growing season. At the end of your annuals' life cycle, remove your spent flowers and vegetables. You can use sheers for this, but ultimately your hands are your best tool. Simply uproot the flower by pulling it from the base of its stem. You can add your discarded annuals to your compost pile.

If your annuals do not automatically reseed themselves, replant the next year using the same steps.

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