Dipladenia, which is also commonly known as mandevilla, is a beautiful and vibrant tropical vine that is widely cultivated for its strikingly colorful and wonderfully fragrant flowers. However, there is often a sense of ambiguity and uncertainty surrounding whether this plant is an annual or a perennial. To be more specific, the truth is that dipladenia is a delicate, yet hardy, woody perennial in zones 10-11, but it behaves like an annual in cooler climates due to its inability to withstand frost and freezing temperatures. We will present is dipladenia annual or perennial?
Overview of Dipladenia
Dipladenia is a genus of flowering plants that is native to tropical regions of South America. There are around 15 species of dipladenia, with some popular garden varieties being:
- Dipladenia sanderi – Also known as red or pink mandevilla
- Dipladenia splendens – Known for white flowers
- Dipladenia boliviensis – Features larger flowers than other varieties
Some of the reasons for dipladenia’s popularity as a garden plant and in containers include:
- Continuous flowering during warm months
- Flowers available in shades of red, pink, yellow, and white
- Climbing vines can grow over 15 feet tall on supports
- Does well in pots and hanging planters
So what determines whether this beautiful tropical vine is grown as an annual or comes back every year as a perennial? The answer lies in winter hardiness.
Is Dipladenia Winter Hardy?
Dipladenia species are native to the warmer parts of South America. Given this tropical heritage, they lack winter hardiness and the ability to survive freezing temperatures or frost. Technically, dipladenia itself is a tender woody perennial plant.
In zones 10 and 11 where freezing weather is rare, dipladenia can continue growing year after year outdoors. The vines regrow quickly each spring to produce the signature abundant blooms they are prized for.
Anywhere colder than zone 10, this tropical plant cannot be expected to return after winter dieback during cold months. Gardeners in zones 8 and 9 may see regrowth depending on the severity of the lowest temperature reached. But in zones 7 and colder, dipladenia will function as an annual plant even if the roots remain alive over winter.
Growing Dipladenia as a Perennial
Gardeners lucky enough to live in frost-free climates can grow dipladenia vines as perennial plants. In zone 10 and warmer, enjoy these plants growing for years to reach impressive proportions over time.
Take steps to help the plants establish deep, extensive root systems. This gives them the best chance to bounce back vigorously each spring:
- Plant in spring once any chance of unusual cold snaps has passed
- Amend soil very well with abundant organic matter
- Allow plants to grow extensive stems and foliage to fuel root system growth
- Water occasionally during first winter if rainfall is lacking
- Cut back vines by one-third to one-half before new spring growth emerges
With this care, expect rambling vines that grow thicker and taller year after year in their perennial status. Blooming gets even more prolific as plants mature in size too.
Managing Dipladenia as an Annual Flower
For most gardeners not in true tropical zones, it works better to treat dipladenia as an annual plant. Focus efforts on getting the most out of the plants during each warm growing season.
Enjoy the vine’s flowers and fast-growing habit as a seasonal annual plant. Here are some tips:
Start New Plants Each Year
Rather than trying to overwinter plants indoors, start with fresh plants either from seed or transplants each spring. Hanging baskets and containers should feature new plantings annual as well.
This avoids the hassle of attempting to keep vines alive indoors over the winter. It also provides the best results, with fast, vigorous growth quickly after planting outdoors.
Annual care does still include amending soil very well and regular fertilizing for happiest growth. But don’t worry about protecting root systems year to year.
Grow in Containers
One advantage of managing dipladenia as an annual is you can grow them beautifully in containers. Hanging pots, urns, window boxes, and other decorative containers showcase trailing vines and abundant blooms.
Focus on containers with these dimensions as minimum sizes:
- 10-12 inches wide/deep for individual vines
- 14 inches or larger for multiple planted vines
Use a high quality commercial potting mix and add polymer moisture crystals into the soil at planting time. Combining compatible plants with similar needs in containers also works well.
Be diligent about watering needs in containers and feeding plants regularly. But with this care, dipladenia thrives all season.
Use Vigorous Varieties
Some dipladenia varieties have a naturally vigorous growth habit that serves annual production well. Choosing these gives the most profuse flowers and tallest vines in a single season.
- Summit series – These sturdy vines shine in containers.
- Mandevilla ‘Alice DuPont’ – Large flowers on long vines.
- Dipladenia X ‘Rio Red’ – Continuous red blooms even in heat.
You can also find specially bred annual dipladenia varieties in seed catalogs and at garden centers. These plants put energy into abundant flowers instead of winter survival.
Protect Fall Growth
Even when managing dipladenia as an annual, you can take steps to prolong the growing season into fall. Protecting fall growth keeps vines flowering well past first frost dates.
Place containers in sheltered areas of gardens:
- Near house walls
- Under taller plantings
- Beside fences or structures
For in-ground plantings, cover vines when colder temperatures arrive. Reusable fabric row covers or plant blankets improve cold resilience. Just keep the cover off during daytime for light and ventilation.
While you will still end up replacing plants next year, this late season protection extends flowering on annual vines.
Caring for Dipladenia Over Winter
Diehard fans living in zones 7-9 do occasionally attempt wintering over dipladenia. While success is mixed, you can follow some general guidelines to give vines the best chance.
Keep in mind plants often return very small and weak compared to fresh nursery transplants. It also takes months before they begin flowering significantly again.
Choose the Best Plants
Do not try overwintering weak, diseased, or insect-plagued vines. Only strong, healthy plants with excellent roots have hope of re-sprouting after storage. Carefully check the roots of container plants or dig up garden vines to examine root health.
Also rely on vigorous varieties bred for overwintering resilience if possible. Dipladenia boliviensis may have the best success into zone 8.
Timing of Pruning & Digging
Pruning vines ahead of winter is key. But cut too early and plants can put on new vulnerable growth when brought inside. Wait until just before your first expected fall frost date.
Similarly, only dig up garden vines once cooler weather has truly set in your zone. Digging while soil is still warm risks active root growth resuming in storage. Handle root balls carefully to avoid further root damage.
Provide Cool, Very Dry Storage
The keys to somewhat successful dipladenia storage are cool temps and very low humidity. Store dormant plants for winter:
- At 45-50°F
- With humidity around 50%
- In complete darkness
Find an unheated basement room, garage, or enclosed porch that maintains these conditions. Only water if soils become fully dry; too much moisture invites deadly root rot diseases. Check storage areas periodically over winter. Discard any rotten or desiccated plants you find rather than later planting them.
Gradually Acclimate Vines
In spring, potted vines or overwintered roots still need gradual re-acclimation before moving outdoors. Allow 2-4 weeks for toughening up cell structures again.
Start by moving plants to a brightly lit, 50°-60°F room. Water very sparingly at first. Then begin leaving storage plants outdoors during milder days, bringing in at night. Harden off this way until ready for transplanting.
Be prepared to offer some protection again late into the next fall and early winter. Dipladenia lack winter hardiness no matter what efforts you make to overwinter them.
Classifying & Using Dipladenia Species
With a better understanding now dipladenia’s place as a perennial vine or seasonal annual, growers can focus on which species may work best for their climate and gardening purposes.
Red & Pink Flowered Varieties
The two red and pink flowering dipladenia species are very popular varieties grown as ornamental vines and container plants. They include:
Dipladenia sanderi
Sometimes listed as Dipladenia splendens or Mandevilla sanderi. This fast-growing woody vine shows off clusters of tubular flowers from summer into fall. Flower colors range from dark red and crimson to lighter pink shades. Ideal for planting on fences and trellises or located in bright garden beds. Often overwintered as a houseplant in marginal zones.
Dipladenia boliviensis
Also called Dipladenia latifolia or commonly red dipladenia. Shiny dark green leaves contrast beautifully with dense clusters of scarlet-red trumpet shaped blooms. A slightly slower grower than other dipladenia, but larger 4” wide flowers. Best resilience for overwintering in zones 8b-9 out of the species. Does very well in containers and hanging baskets.
Growing White Flowered Dipladenia
White flowering dipladenia vines actually belong to their own separate species:
Dipladenia amoena
The flowers may not be as prolifically clustered, but make up for it in size. Individual trumpet-shaped white blooms grow over 5 inches long, with a subtly frilled shape. Dark waxy leaves set off the clean white beautifully. Typically not as vigorous a grower as pink/red varieties. Shines best given some shade, especially during hot summer months. More success overwintering than D. sanderi or D. boliviensis.
Choosing the Best Variety for You
Consider the size potential, growth rate, optimal climate, and availability of varieties in your region. Those targeting overwintering plants should focus on D. boliviensis or D. amoena first.
Container gardeners appreciate profuse bloomers like the Summertime Blues or Rio series. Busy gardeners often favor the lower maintenance white species for trellises and garden beds.
You can also easily find many hybrids in nurseries and catalogs. These mix traits of multiples parent dipladenia species, expanding color options too.
No matter if treating as annuals or perennials, proper selection sets up success with these wonderful vines.
Dipladenia Care Through the Seasons
Caring for dipladenia does change some depending on if you are growing vines as annuals or perennials. But some core maintenance practices remain the same in either case. Being consistent with good dipladenia care results in spectacular flowering displays.
Spring Care Tips
Spring kickstarts the growing season, so focus care on promoting vigorous vine growth:
- Plant fresh nursery vines or overwintered plants after danger of frost is past
- Pinch back tips of younger shoots to encourage bushy growth
- Install supports early for climbing vines before heavy growth starts
- Water whenever the top few inches become dry to touch
- Begin fertilizing every 2-3 weeks with a balanced liquid feed
- Scout regularly for early signs of pests like spider mites or mealybugs
Summer Maintenance Mode
The summer season calls for sustaining fast growing vines and responding to challenges of heat and drought:
- Water container plants more than in-ground vines when soils become dry
- Spread an organic mulch layer to cool roots and retain moisture
- Stake and loosely tie long flexible vines as needed to supports
- Prune back wayward or damaged vines interrupting desired growth habit
- Increase feeding to every 7-10 days to fuel flowering
- Monitor for common pests like aphids, whiteflies, and thrips on foliage/flowers
Be ready to respond if drought stress becomes visible through drooping or yellowing vine leaves. Damage can happen fast in pots or sandy soils.
Fall Carefor Ongoing Blooms
Keep vines flowering long into fall with these maintenance practices:
- Reduce feeding frequency for container vines by mid September
- Cut vines back to desired overwintering length on first fall frost threat
- Lower watering duration and frequency significantly for garden plants by mid October
- Place removable covers over plants whenever hard freeze warnings arise
- Prepare vines in zones 8/9 for overwintering process by month’s end
- Store containers in protected areas of landscapes until heavy frost kills them back
Adjust fall practices based on your average first freeze date and winter severity. Aim to squeeze the most possible flower production out of vines before cold stops growth.
Troubleshooting Common Dipladenia Problems
Even when given proper care, issues can sometimes plague dipladenia vines. Stay alert for potential problems and be ready to take action at first signs. Rapid response gives the best chance of restoring plant health and keeping diseases from spreading.
Yellow Leaves & Stunted Growth
Insufficient nutrients often causes dipladenia leaves to lighten to yellow or growth to slow down. This happens most in containers with poor soil or during heavy flowering periods. Mix a balanced fertilizer into soils per label directions or apply a liquid feed immediately. Prune back struggling vines to allow regrowth.
Overwatering can also lead to nutrients leaching from soil. Check if roots are saturated and let excess moisture drain fully from containers. Only resume normal watering once the top few inches of soil become dry.
And don’t neglect the basics either – yellowing often signals too little sunlight or battered root systems.
Wilting Foliage & Drooping Vines
Leaves and vines that wilt or droop can alarm growers. But don’t panic right away. Some causes just need temporary intervention:
- Overheating – Move containers out of blistering sun or provide shade for garden vines midday. Water foliage to cool plants until temperatures moderate seasonally.
- Under Watering – Parched containers dry out fastest, but even garden vines get thirsty. Slowly soak root zones until drainage happens from containers. Or run irrigation until moist at least 6 inches down around garden dipladenia.
- Over Watering – If soils stay soggy for multiple days or roots appear dark brown/rotten, drainage issues are drowning vines. Repot struggling container plants in fresh mix or amend garden soil with compost.
Seek other advice if wilting worsens over weeks and vines decline despite your corrective care. Underlying disease or pest issues may require ID and stronger treatment.
Chewed Foliage or Distorted Growth
Keep a close eye out for insects like spider mites, aphids, or thrips when new damage appears:
- Check leaf undersides first since pests often hide there
- Use a magnifying glass to look for tiny sucked specs, tiny larvae, or thin webs tying leaves together
- See if tiny white dots representing eggs are clustered along veins or joints between stems
Mimosas flowers, known for their delicate beauty, conceal a vulnerability to infestations that can compromise their health and appearance. To safeguard these blossoms, it’s essential to arm yourself with knowledge on everything from their intricate anatomy to the nuanced care they require. Start control measures at the earliest signs of infestation before it expands, employing gentler options like strong hosing off vines, insecticidal soap, or neem oil for mild cases limited to a few leaves. However, for more severe spreading instances identified early enough to save vines, it becomes imperative to bring out chemical insecticides, acting as a last line of defense against the potential devastation.
But discard completely infested plants found too late as a loss. Removing them protects any nearby plants from becoming newly infected. Don’t try saving or overwintering pest-ridden vines.
