7 Methods to Promote Bougainvillea Blooms

To increase bougainvillea flower numbers and stimulate flowering, place bougainvilleas in full sun, but make sure they get fewer than 12 hours of daylight as they are short-day plants. Watering potted bougainvillea once a week creates an optimal balance between water and drought stress, which promotes more flowering.

Native to Brazil, bougainvillea is native to Brazil and fewer hours of sunlight will stimulate flowering because the days are shorter, suggesting that bougainvillea is now the perfect time to bloom, matching the appropriate environmental conditions for that time of year.

Shorter days are one of the most influential factors in increasing bougainvillea flowering. Read on to learn 7 ways to increase your bloom count and prolong your bloom display.

1. Bougainvilleas bloom more when day length is shorter

Bougainvillea is something different! Although they need full sun, they bloom more frequently when the days are shorter.

This particular characteristic is the result of adaptation to tropical environments, where the days are shorter than the nights during the dry season, suggesting that bougainvillea is now the best time of year to bloom.

Therefore, it is appropriate to reproduce these conditions. Bougainvillea likes at least 12 hours of uninterrupted darkness to flower.

Therefore, finding the best location to plant bougainvillea can be a challenge for those living in northern latitudes.

For example, in the UK there can be up to 15 hours of sunshine per day, while in New York the maximum is 16 hours.

Make sure there are no artificial lights to disturb the preferred 12 hours of darkness at night.

If you’re particularly keen (like me), you can use bells, garden fleece, or even an umbrella to shade your bougainvillea to recreate its natural conditions for flowering.

It’s important to note that bougainvilleas still need full direct sun to bloom, but daylight hours should be limited to no more than 12 hours.

Fortunately, if your climate has mild winters, for example, bougainvilleas can bloom year-round. B. For those who live in a Mediterranean climate, but regardless of location, they bloom more in 12 hours or more of darkness.

2. Water Less Often to have More Flowers

Bougainvilleas love heat and drought—they’re native to Brazil, after all!

Therefore, it is important not to water them too often.

Bougainvillea is drought tolerant and should be treated a little differently than a hydrangea and rose display, but more like a lavender and Mediterranean herb collection.

Watering potted bougainvilleas is usually done once a week, but stop watering if the soil feels soggy to finger depth. The soil should feel like it dries out before watering again.

Mature bougainvillea vines planted in garden borders usually don’t need watering unless they are small plants that haven’t yet established a root system or are dealing with an unusual drought.

3. Direct sunlight promotes bougainvillea flowering

Direct sunlight is a must for bougainvilleas. As you can imagine, the plants are abundant in their native Brazil – so it’s important to do your best to recreate these conditions in your garden wherever you are.

A good idea is to grow bougainvilleas in pots. This allows you to move them to a sunny location during the changing seasons.

Alternatively, if you live in a non-Mediterranean environment, these potted plants can also be kept indoors during the winter. This will protect the plants from the cold and possible frost.

(Bougainvilleas often lose their leaves in winter if the climate is not optimal. However, with proper care, the leaves can grow back in the spring.

Remember, it is important to take into account the shorter day length for more flowering, as well as the intensity of the sun.

4. Warmer temperatures promote flowering

Warmer temperatures mean bougainvillea bloom times will increase. This is especially important for those who live in colder climates.

Ideal nighttime temperatures should be around 18°C ​​(65°F). However, the vitality of bougainvillea is relatively tenacious, and its adaptability is also very good. They can tolerate cooler (but not cold!) nighttime temperatures and still show plenty of flower buds.

Place your bougainvillea in a sheltered location so cold winds don’t stress the plants.

If the nights are too cold, the plants get stressed. In colder climates, it is important to grow bougainvilleas in pots and move them indoors over winter, as they cannot tolerate severe frost.

Place the pot in a sunny window seat so that it absorbs the heat and sunlight of the house for optimal flowering.

5. Fertilize less, bloom more

Using too much fertilizer can cause your bougainvillea to grow lush green leaves at the expense of blooms!

When your bougainvillea is growing well and planted in a border, it needs little to no fertilizer. They thrive in this location probably because they have well-drained soil rather than loamy soil (see point 6 on drainage).

If your bougainvilleas are in pots, it makes sense to use a half-strength all-purpose fertilizer to ensure they have the proper nutrients they need to bloom and not too much nitrogen (the chemical that produces lush green leaves). Fertilize in early spring once the threat of cold weather has passed. Remember, bougainvilleas are not hardy!

Personally, I have had good results stopping fertilizing when day length gets shorter, as the “stress” of reduced available nutrients also stimulates flowering.

Likewise, drought stress can cause bougainvillea to prioritize reproduction (via flowering) over leaf, root, and vine growth.

6. Well-drained soil favors flowering

As mentioned earlier, bougainvilleas are well adapted to growing in well-drained soil. They cannot tolerate boggy, overwatered soils because the roots will rot. For increased flowering, make sure your bougainvilleas have good drainage.

Add garden debris and make sure the soil drains well. This will help replicate the well-drained soil conditions of the bougainvillea in its native Brazil.

If planting in a pot, make sure there are drainage holes in the bottom of the pot so that excess water can drain effectively after watering. For this reason, pots may be the preferred location for bougainvilleas because you have more control over drainage than garden borders.

7. Prune bougainvillea for more blooms

Bougainvillea blooms in the new season, not in old wood. Therefore, to increase bougainvillea blooms, it is important to prune bougainvilleas in late winter or early spring, before spring growth begins.

If you don’t prune your bougainvillea, they will become leggy and produce fewer flowers. Therefore, tactical cuts are always recommended.

Pruning should not be too harsh as this wastes too much energy growing new shoots and tendrils. Light pruning, however, promotes flowering best and helps keep your bougainvillea in shape on a trellis or support structure.