How Long Does It Take for Mandevilla Seeds to Germinate and Grow?

Mandevilla is a popular tropical vine grown for its large, showy flowers. While commonly propagated by cuttings, some gardeners enjoy the challenge of growing mandevilla from seeds. If you want to try propagating mandevilla from seed, you probably wonder – how long does it take for the seeds to sprout and produce mature vines?

Mandevilla seeds require careful handling and optimal growing conditions to germinate successfully. But with proper care you can expect seedlings to emerge within 1-2 months. It takes 2-3 months for vigorous vines to develop from seeds. Here is a detailed timeline so you know what to expect when growing mandevilla from seed.

Collecting and Storing Mandevilla Seeds

The first step is collecting ripe mandevilla seeds when seed pods dry and turn brown on the plant. You’ll recognize seed pods by their long, skinny, upside-down V-shape. Or you can store unopened pods in paper bags until ready to remove the seeds.

Leave the seeds to dry for another one to two weeks after you’ve picked them. When seeds are completely dry, they should be kept in a cool, dry place in a container that doesn’t let air in.

Seeds can be planted for three to four months after they have been properly dried and stored. Throw away any that get moldy or brown while they’re being stored. Only fresh seeds that have been stored properly will grow quickly.

Preparing for Planting

Before planting mandevilla seeds, take these steps to increase germination success:

• Soak seeds in room temperature water for at least 12 hours before planting.

• Prepare a well-draining starting mix of half potting soil, half perlite or coarse sand. Moisten before planting.

• Use containers with drainage holes and a seed starting humidity dome or plastic wrap.

• Provide bottom heat of 70-80°F from heat mats, hot pads, or appliances.

Warmth, humidity, and pre-soaking hastens germination time. Group seeds close together for even moisture and heat retention.

Sowing Mandevilla Seeds

Follow these directions when planting mandevilla seeds:

• Fill containers with moistened seed starting mix, leaving 2 inches at the top.

• Sprinkle seeds on the surface without burying them. Just press gently into the soil.

• Cover with plastic wrap and place on 70-80°F bottom heat sources.

• Keep soil moist but not saturated. Provide bright, indirect light.

Warmth and constant surface moisture helps mandevilla seeds sprout best. Water from below to keep the humidity high until the sprouts come up so that the seeds don’t get washed away.

Germination Timeline

Under optimal growing conditions, follow this timeline for mandevilla seed germination:

• 1-4 weeks: Seeds swell and embryos begin to grow. No visible changes are seen.

• 4-6 weeks: Tiny white sprouts emerge from seeds. Growth is slow at first.

• 6-8 weeks: Seedlings form 2-3 true leaves and start vining. Bottom heat can be reduced.

• 2-3 months: Vigorous, established vines ready for transplanting into individual pots.

After planting, the first seedlings should come up in one to two months. It takes two to three months for vines to grow into mature plants that grow quickly. If the seeds are dry or not warm enough, the process takes longer. When they are ready to be potted up, healthy seedlings will be over 6 inches tall.

Caring for Mandevilla Seedlings

Once seedlings emerge, provide excellent care for robust growth:

• Keep soil moist but not soaked as plants establish. Water when surface dries out.

• Gradually expose seedlings to lower humidity levels. Remove domes once established.

• Feed biweekly with balanced fertilizer diluted to half strength.

• Ensure warm days around 75°F and nights above 65°F for steady growth.

• Transplant seedlings into individual 4 inch pots once vines are 3-4 inches tall.

• Shift into the garden or larger containers when vines reach 8-12 inches tall.

With proper light, water, nutrition and warmth, mandevilla seedlings will rapidly gain size and long vining stems.

Troubleshooting Germination Issues

If mandevilla seeds are slow to sprout or fail to grow, some potential problems are:

• Old, non-viable seeds – fresh seeds sprout best

• Incorrect seed storage – drying out or humidity reduces viability

• Planting too deep – seeds need light to germinate

• Improper watering – seeds need consistently moist soil

• Lack of bottom heat – aim for 70-80°F for fast germination

• Low humidity – seeds need high humidity from domes/plastic

• Insufficient light – some sunlight is needed for growth

Adjust your methods to remedy any issues to improve germination success when starting mandevilla from seeds.

Tips for Growing Mandevilla from Seed

Follow these tips to increase your chances of success propagating mandevilla from seed:

• Start with high quality, fresh seeds used within 4 months of harvest.

• Provide consistent 70-80°F bottom heat until seeds sprout.

• Soak seeds before planting and keep soil lightly moist.

• Use a seed starting humidity dome or plastic wrap.

• Once sprouted, grow seedlings under plant lights 12-16 hours daily.

• Transplant seedlings early into 4 inch pots to avoid rootbound plants.

• Pinch back tips to encourage bushy, full vines.

• Move vines outdoors once well established.

• Allow 2 months minimum from seed to transplant-ready seedlings.

With excellent care, you can successfully grow beautiful mandevilla vines from seeds. Just be ready for a longer wait compared to buying young nursery plants.

When to Expect Flowers on Seeded Mandevilla

Don’t expect quick blooms on mandevilla started from seeds. Here’s the typical flowering timeline:

• Vines from winter/early spring seeds usually bloom their first summer, 3-4 months after transplanting outside. However, flower production is often sparse the initial year.

• Plants started in summer may not bloom until the following year. Growth is focused on establishment.

• Full flowering occurs in the second year for overwintered vines started from seeds.

• Container grown plants tend to flower sooner than in-ground vines.

Be patient – mandevilla seedlings prioritize growth and development before reaching mature flowering size. But the wait is worth it for vines you grew yourself from seed!

Frequently Asked Questions

Here are answers to some common questions about growing mandevilla from seed:

What conditions are needed for mandevilla seeds to sprout?

Mandevilla seeds need consistently warm (70-80°F) soil temperatures, high humidity, and lightly moist soil for successful germination.

How deep should I plant mandevilla seeds?

Just press mandevilla seeds into the starting mix surface without covering them. They need light to germinate and can rot if buried too deeply.

When can I transplant mandevilla seedlings?

Wait until seedlings are 3-4 inches tall with 2-3 true leaves before transplanting into individual containers. Shift them into the garden once they reach 8-12 inches tall.

How do I encourage bushy growth in mandevilla seedlings?

Pinch back young shoots cautiously once plants are established to promote side branching and fuller vines. Avoid over-pinching which can stunt growth.

Will hybrid mandevilla seeds grow true-to-type?

Hybrids are less likely to grow true from seed. The resulting vines may differ in leaf shape, habit, or flower color from the parent plant.

Conclusion

Starting mandevilla from seeds requires more time and care than buying potted nursery plants. But watching your vines grow from seed to flowering is incredibly rewarding. Follow proper techniques for collecting, storing, and planting seeds. Provide optimal conditions for germination and grow seedlings well. In 2-3 months, you’ll have beautiful mandevilla vines to highlight your garden. With excellent care, mandevilla seeds can successfully produce gorgeous blooming vines.