What is a Tender Perennial? A Guide to Caring for These Heat-Loving Plants

As a gardener, you’re likely familiar with annuals and perennials. But tender perennials occupy a sort of in-between space They have qualities of both annuals and perennials, which can make them confusing Read on to learn exactly what a tender perennial is along with tips for growing these beautiful but temperamental plants.

Defining Tender Perennials

First let’s break down the term itself. A perennial plant is one that lives for multiple years often 3 or more. Perennials regrow from their root system each spring. An annual completes its entire lifecycle of germination, growth, flowering, and death within a single season.

Tender perennials, then, are perennials that aren’t winter hardy. They can’t withstand freezing winter temperatures in some climates. Their above ground growth dies back with cold weather, but the roots survive if given proper overwintering care.

So tender perennials are not true annuals since the plant itself can live for many years. But in climates with cold winters, they function more like annuals since the top growth must be replanted each spring.

Examples of Popular Tender Perennials

Some classic examples of tender perennials include:

• Bulb plants: dahlias, canna lilies, calla lilies, elephant ears
• Tuber plants: begonias and caladiums
• Herbs: rosemary, thyme, basil, cilantro
• Vines: Mandevilla, passionflower
• Shrubs: hibiscus, lantana, bougainvillea

These plants all share origins in tropical, subtropical, or Mediterranean climates where winters stay warm. When grown as annuals in colder zones, gardeners must replant them each year.

The Benefits of Tender Perennials

While tender perennials require more effort in climates with cold winters, they offer unique advantages:

• Fast growth: Tender perennials tend to grow quickly and fill out compared to hardy perennials. You’ll get a lush look faster.

• Long bloom seasons: Many tender perennials like Mandevilla produce flowers over many months in summer and fall.

• Tropical look: Large leaves, colorful flowers, and dramatic shapes provide exotic, tropical flair.

• Fragrance: Herbs and shrubs like rosemary and lantana add wonderful scents to gardens and containers.

• Annual flexibility: You can redesign displays each year since the plants must be replaced annually.

Caring for Tender Perennials in the Garden

Tender perennials need some specialized care to help them thrive in areas with cold winters. Here are some key tips:

• Plant after the last frost date when soil and air temperatures have warmed. Avoid shock from cold soils.

• Give them a long growing season by starting indoors from seed or cuttings 2-3 months before your outdoor planting date.

• For the best growth, provide plenty of sun and rich, well-draining soil. Fertilize regularly.

• Water tropical plants frequently to replicate humid rainforest conditions. Mediterranean types need less water.

• In fall, protect plants by covering or moving containers indoors if frost threatens.

• Dig up bulbs, corms, and tubers after foliage dies back and store them in a cool place for winter.

• Take cuttings of non-bulbous plants in late summer to propagate for the next year.

With the right care, you can enjoy fast-growing tender perennials each summer. Just be prepared to replace or propagate them annually.

Overwintering Tender Perennial Bulbs, Corms, and Tubers

One challenge when growing tender perennials is how to overwinter them. While the foliage dies back, the underground structures like bulbs and tubers remain alive. Storing them properly is key to success.

Here are some tips for overwintering dormant tender perennial plants:

• Allow foliage to die back completely after the first hard frost.

• Dig up bulbs carefully and allow to dry and cure for 1-2 weeks in a frost-free location.

• Remove any remaining foliage or stems and brush off caked dirt.

• Sort by plant variety and discard any bulbs that are diseased or damaged.

• Place bulbs in breathable trays or mesh bags filled with peat, vermiculite, sawdust, or sand.

• Store in a dark, cool (40-60°F), humid location like a basement or unheated garage.

• Check periodically and remove any bulbs that get moldy or start to rot.

• In spring, plant bulbs outdoors after the danger of frost has passed.

Proper curing, storage conditions, and ventilation prevents diseases so bulbs will be vigorous when replanted.

Overwintering Non-Bulbous Tender Perennials

Tender perennials that don’t form bulbs require different overwintering methods. Here are some options:

• Keep as houseplants: Prune back leggy growth and maintain indoors over winter near a sunny window.

• Take cuttings: Root cuttings in summer to propagate new plants and discard the parent plant.

• Store dormant in cool location: Prune back top growth of plants like brugmansia and allow roots to go dormant in a cool basement over winter.

• Treat as annuals: Simply allow frost to kill the foliage and start new plants from seed or transplants next year.

Consider thespecific plant’s needs, your climate, and available space when deciding the best overwintering method.

How to Plant Tender Perennials in Spring

Once properly stored for winter, it’s time to wake up tender perennials and replant in spring. Follow these tips:

• In early spring, start bringing bulbs and tubers out of storage to a warm indoor place. This allows them to break dormancy gradually.

• Plant the bulbs outdoors after all danger of frost has passed. Work in compost and organic fertilizer when planting.

• Water the bulbs well after planting to remove any air pockets and settle the soil. Continue watering when soil dries out.

• Shelter newly sprouted growth if any unusual late cold snaps occur to prevent damage.

• Remove any flower buds the first year to allow the plants to focus energy on establishing roots and foliage.

With proper planting care, stored bulbs and tubers will reward you with vigorous growth and flowers in the current season.

Troubleshooting Common Tender Perennial Problems

Growing tender perennials presents some unique challenges. Here are solutions to a few possible issues:

• Poor survival over winter: This is often due to improper curing, storage conditions that are too warm, wet, or humid, or lack of ventilation resulting in rotting.

• Failure to sprout: If bulbs don’t sprout in spring, it could be due to over-drying prior to storage, damage during digging, or death during storage because conditions weren’t cool enough. Discard un-sprouted bulbs.

• Small flowers and foliage: Inadequate sunlight, poor soil, or insufficient water and fertilizer can lead to poor growth.

• Rot during storage: Excess moisture during curing or storage will quickly cause bulbs and tubers to rot. Keep them dry with plenty of air circulation.

With attention to proper care, you can minimize problems and keep tender perennials thriving as annual additions to your garden.

Where to Buy Tender Perennials

You can find a great selection of tender perennials at most garden centers and nurseries, garden stores, or online retailers. Shop early in spring for the best availability.

Many tender perennial bulbs and tubers can be ordered by mail order or found at big box home improvement stores as well. Smaller or more unusual varieties may only be available from specialty growers.

If you don’t want to fuss with storage, simply buy new plants each year. For the widest selection, shop reputable nurseries that focus on tropical and subtropical plants.

Enjoying Gorgeous Tender Perennials

Don’t be discouraged if you adore tropical, heat-loving plants but live where winters bring freezing temps. With proper planning and care, you can grow beautiful tender perennials as annuals. Their flashy flowers and colorful foliage bring big visual impact quickly during the warm season. Just be diligent about providing the right conditions and overwintering care to help these delicate plants thrive each year.