Plant Care Guide

Mandevilla
(Tropical Rocktrumpet)

Mandevilla spp.

Showy, trumpet-shaped blooms and twining vines make mandevilla a summer head-turner for trellises, arbors, mailboxes, and containers. Give it sun, warmth, and steady moisture and it will reward you with nonstop color—this guide distills practical mandevilla care so you can enjoy reliable flowering all season and smooth overwintering.

Watering Requirements

Bloom performance tracks closely with even moisture—too dry and buds stall, too wet and roots sulk. Aim for “moist but never soggy” and let the top layer of soil dry slightly between waterings.

Watering Schedule

  • Spring/Summer (active growth): Water when the top 1–2" are dry (often every 3–5 days outdoors; 5–7 days in bright indoor spots).
  • Fall: Reduce frequency; allow the top 2" to dry before watering.
  • Winter (indoors/dormant): Lightly water every 10–14 days to keep soil just barely moist.

Signs of Overwatering

  • Yellowing leaves from the base, limp growth, sour-smelling soil

Signs of Underwatering

  • Wilting between waterings, crispy leaf edges, buds drying and dropping

Pro Tips

Water slowly and deeply until a bit drains out, then empty saucers—deep soaks encourage wider root systems and more reliable flowering for this care of a mandevilla essential.

Light Requirements

Flower power is light-powered: mandevilla blooms best with abundant direct sun, tempered in extreme heat. Provide at least 6 hours of sun daily; in very hot climates, afternoon shade prevents leaf scorch.

Ideal Placement

  • Outdoors: Full sun with optional dappled afternoon shade in peak summer.
  • Indoors/Overwintering: Bright, indirect light near a south or west window; supplement with grow lights if days are short.

Too Much Light/Heat

  • Bleached patches or crispy tips—add sheer shade during the hottest hours

Too Little Light

  • Long internodes, few flowers, pale foliage—move to a brighter site

Pro Tips

Rotate containers ¼ turn weekly so all sides get sun; consistent light keeps vines even and buds forming continuously—core to care for mandevilla plants.

Soil and Potting

Roots want air and steady moisture, so use a fast-draining mix that holds a little water but never stays wet. Slightly acidic to neutral pH is ideal.

Best Potting Mix

  • 2 parts high-quality potting mix
  • 1 part perlite or pumice (drainage)
  • 1 part fine bark or coco chips (structure)

Container Notes

  • Choose pots with generous drainage; size up just one step when roots circle the pot.
  • For in-ground beds, amend heavy soil with compost and grit for drainage.

Pro Tips

Set a trellis at planting time—training is far easier when growth is young and flexible.

Fertilizing

Regular, modest feeding keeps blooms coming without salt stress. Prioritize phosphorus during peak bloom and keep nitrogen moderate.

Fertilizer Schedule

  • Spring–Early Fall: Every 2–3 weeks with a balanced or bloom-forward liquid feed at ½ strength.
  • Slow-release option: Incorporate a granular slow release in spring; supplement lightly mid-summer.
  • Winter: Pause feeding during indoor rest.

Deficiency Clues

  • Lots of leaves, few flowers → too much nitrogen
  • Pale foliage/stalled buds → needs balanced nutrients

Pro Tips

Flush containers with plain water every 6–8 weeks to prevent fertilizer salt buildup that can burn leaf margins.

Pruning and Training

Pruning maintains shape, promotes branching, and concentrates energy on new, flower-bearing growth. Training directs vines where you want the show.

Pruning Guidelines

  • Late Winter/Early Spring: Cut back by up to ⅓ before growth resumes (flowers form on new growth).
  • During Season: Pinch tips lightly to encourage side shoots and more buds; remove spent or tangled vines.

Training Tips

  • Tie vines loosely to trellises with soft ties; spiral stems upward for even coverage.
  • For a fuller base, pinch young shoots at 12–18" tall.

Pro Tips

Wear gloves; the milky sap can irritate skin.

Common Problems and Solutions

Yellow leaves + wet mix → Overwatering/poor drainage. Let top soil dry, improve aeration, ensure drainage holes are open.

Buds drop → Fluctuating moisture, low light, or low humidity. Water evenly, brighten location, boost RH.

Pests (aphids, mites, whiteflies, scale) → Rinse foliage, then treat with insecticidal soap or neem weekly until clear.

Few blooms → Insufficient sun or excess nitrogen. Increase light to 6–8 hrs and switch to bloom-forward feeding.