Phalaenopsis Gigantea

If you’re looking for a truly spectacular orchid to add to your collection, the Phalaenopsis gigantea should be at the top of your list. Known for its stunningly large orchid blooms, this plant is a giant in every sense of the name.

It’s not the easiest orchid to find or grow, but its impressive foliage and massive flower sprays make the effort worthwhile. Let’s look at what makes this species so special and how you can succeed with it.

Unlike the common moth orchids (Phalaenopsis) you see in stores, Phalaenopsis gigantea is a species orchid. This means it grows naturally in the wild, specifically in the lowland forests of Borneo. Its name, “gigantea,” is no exaggeration.

Before it even flowers, the plant commands attention with its massive, leathery leaves. They can grow over two feet long and nearly a foot wide. The plant itself can become quite large, sometimes spanning four feet across. This size makes it a stunning centerpiece in any greenhouse or bright indoor space.

What Makes Its Flowers So Impressive?

The blooms are the main event. While a standard phalaenopsis might have flowers 3-4 inches across, Phalaenopsis gigantea produces blooms that can easily reach 4 to 5 inches in diameter. A single flower spike can carry dozens of these large, rounded flowers.

The colors are typically a creamy white or pale yellow, densely covered with attractive spots or blotches in brown or maroon. The flowers also have a lovely, subtle fragrance. The combination of size, quantity, and pattern is what creates its breathtaking display.

Ideal Growing Conditions for Your Giant

To keep your Phalaenopsis gigantea healthy and encourage those famous blooms, you need to mimic its natural habitat. Here are the key factors to get right.

Light Requirements

This plant needs bright, indirect light. Think of the dappled sunlight under a forest canopy.

An east-facing window is often perfect.
A shaded south or west window can also work well.
Too much direct sun will scorch its large leaves, causing bleached or brown patches.
If the leaves turn a very dark green, it’s a sign it needs more light.

Temperature & Humidity

As a lowland tropical plant, it enjoys warmth and consistent moisture in the air.

Aim for daytime temperatures between 75-85°F (24-29°C).
Nighttime temps can drop to 65-70°F (18-21°C).
Try to maintain humidity levels above 50%. A humidity tray or a room humidifier is very helpful, especially in dry homes.
Good air movement is crucial to prevent fungal issues in such humid conditions.

Potting Mix and Potting

This orchid is usually grown in a very coarse, fast-draining medium. It’s often mounted on a slab of cork or tree fern because of its large, spreading habit, but it can be potted.

Excellent mixes include large chunks of bark, horticultural charcoal, and perlite.
Choose a wide, shallow pot that can accommodate its tendency to grow sideways.
Repot only when the media breaks down, about every 2-3 years, and be gentle with its sensitive roots.

A Step-by-Step Watering and Feeding Guide

Proper watering is the most common area where growers run into trouble. Here’s a simple routine to follow.

Check the Medium: Let the potting mix or the roots on a mount approach dryness before watering. The thick leaves store water, so its better to err on the side of under-watering than over-watering.
Water Thoroughly: Take the plant to the sink and flush water through the mix until it runs freely from the drainage holes. If mounted, soak the entire root mass for 5-10 minutes.
Drain Completely: Ensure no water is left sitting in the crown (where the leaves meet) or in a pot’s saucer, as this leads to rot.
Fertilize Weekly: During active growth (spring through fall), use a balanced orchid fertilizer at 1/4 strength every time you water. The saying “weekly, weakly” is a good rule.
Flush Monthly: Once a month, water without fertilizer to rinse away any salt buildup from the feed.

Encouraging Those Massive Blooms

Mature plants can produce those stunningly large orchid blooms, but they need a slight nudge. The main trigger is a consistent temperature drop.

In the fall, try to provide a noticeable difference between day and night temperatures. A drop of about 10-15°F (5-8°C) is ideal. If you grow it indoors, this might mean moving it to a slightly cooler room at night for several weeks.

Once you see a flower spike emerging, you can stake it gently. Be patient, as the spike can take many months to develop and open all its buds. Avoid moving the plant’s orientation once the spike is growing, as the buds will twist toward the light.

Common Problems and Simple Solutions

Even with great care, you might encounter an issue. Here’s how to troubleshoot.

Leaf Wrinkling: This is usually a sign of underwatering or root loss. Check the root system. If roots are dead (mushy or papery), repot into fresh medium.
Brown, Soft Spots on Leaves: This is crown or stem rot, often from water sitting in the leaf joints. Improve air flow and always dry the crown after watering.
No Flowers: The most likely culprits are insufficient light or lack of a temperature drop. Review its growing conditions.
Pests: Watch for scale, mealybugs, or spider mites. Treat early with insecticidal soap or neem oil, wiping the large leaves regularly helps prevent infestations.

Propagating Phalaenopsis Gigantea

You can propagate this orchid, but it requires patience. The most reliable method is from seed in a lab. For home growers, the best chance is if it produces a keiki (a baby plant) on an old flower spike or at the base.

Wait until the keiki has several leaves and roots that are at least 2-3 inches long.
Using a sterile tool, cut the keiki away from the mother plant, keeping its roots intact.
Pot the keiki in a small container with a fine orchid mix, keeping it slightly more humid than usual as it establishes.

FAQ About Phalaenopsis Gigantea

How often does Phalaenopsis gigantea bloom?

A mature, healthy plant typically blooms once per year. The flowering period can last for several months due to the sequential opening of the many buds.

Is Phalaenopsis gigantea rare?

Yes, it is considered a collector’s orchid. You won’t find it at most garden centers. Look for it at specialized orchid nurseries, shows, or from reputable online vendors.

Can I grow this orchid in my normal house?

You can, if you have a very bright space (like a sunroom or large window) and can manage humidity. Many growers find they have the most succes in a greenhouse or under grow lights.

Why are the leaves on my giant orchid turning yellow?

One yellowing bottom leaf is normal as it ages. Several yellowing leaves, however, can indicate overwatering, poor roots, or a severe nutrient deficiency. Check your watering habits first.

How big does the plant actually get?

In cultivation, a well-grown Phalaenopsis gigantea can easily have a leaf span of 3 to 4 feet. It’s a space commitment, so plan accordingly.

Growing Phalaenopsis gigantea is a rewarding long-term project for any orchid enthusiast. Its grand scale and spectacular flowers offer a unique experience different from common hybrids. By providing steady warmth, bright indirect light, and careful watering, you’ll be able to enjoy its impressive foliage for years. And when it finally rewards you with a spray of its stunningly large orchid blooms, you’ll know all the effort was truly worth it.