Caring for geraniums indoors is surprisingly simple with the right light, water, and feeding. Provide a sunny spot, water when the top inch of soil is dry, and feed regularly during growth for vibrant blooms and healthy leaves. Follow these essential tips for happy indoor geraniums.
Welcome, fellow plant enthusiasts! Are you dreaming of colorful blooms brightening your home, even when the weather outside is drab? Geraniums are fantastic plants, known for their cheerful flowers and lovely scents. Many people think they are strictly outdoor plants, but with a little know-how, you can absolutely enjoy them thriving indoors year-round. It can feel a bit daunting at first, especially if your past attempts at indoor gardening haven’t gone as planned. Don’t worry! Caring for geraniums indoors is a rewarding and achievable goal for any beginner. We’ll break down exactly what your geraniums need, step-by-step, so you can watch them flourish. Get ready to fill your home with beautiful color and fragrance!
Why Grow Geraniums Indoors?
Bringing geraniums inside offers a delightful way to extend their blooming season and enjoy their beauty year-round. Imagine vibrant pops of red, pink, white, or purple gracing your windowsill throughout the colder months, a welcome splash of color against a gray sky. Beyond their aesthetic appeal, many geranium varieties, particularly scented-leaf geraniums (often mistakenly called “geraniums” but are actually Pelargoniums), release fragrant oils when their leaves are brushed. These natural scents can be lovely additions to your home environment, some even used in DIY potpourri or culinary recipes. Growing them indoors also allows you to protect them from harsh frost and pests that might trouble them outdoors, ensuring a healthier, more consistent display.
Choosing the Right Geranium Variety for Indoors
Not all geraniums are created equal when it comes to indoor living. While some “true” geraniums (hardy or perennial geraniums) can be grown indoors, the most common and rewarding varieties for houseplants are actually Pelargoniums. These are the zonal, ivy-leaved, and regal (Martha Washington) pelargoniums that most people associate with colorful patio planters and window boxes. For indoor success, consider these types:
- Zonal Pelargoniums: These are the workhorses. They have distinct zonal markings on their leaves and produce large clusters of flowers. They are relatively compact and easy to manage indoors.
- Ivy-Leaved Pelargoniums: With trailing stems, these are perfect for hanging baskets or placing on shelves where they can cascade down. Their flowers often have a slightly more delicate appearance.
- Regal Pelargoniums (Martha Washington Geraniums): These are known for their spectacular, large, often ruffled flowers in a wide range of colors. They can be a little fussier than zonal types but are incredibly rewarding when they bloom.
- Scented-Leaf Pelargoniums: If you love fragrance, these are a must. While their blooms are often smaller, their leaves emit wonderful scents like rose, lemon, mint, or cinnamon. They are remarkably robust as houseplants.
When selecting a plant, look for one that is short, bushy, and covered in healthy green leaves. Avoid plants that are tall and leggy, with yellowing leaves or signs of pests. A healthy plant going into your home has the best chance of thriving.
Essential Care Requirements for Indoor Geraniums
Indoor geranium care boils down to a few key elements: light, water, soil, temperature, and feeding. Getting these right will set your plants up for success.
1. Light: The Golden Rule
Geraniums are sun-loving plants. Indoors, this means they need the brightest spot you can offer. South-facing windowsills are typically ideal, as they receive the most direct sunlight throughout the day. East or west-facing windows can also work, but they might offer slightly less intense light. Rotate your plant every week or so to ensure all sides receive adequate light, preventing it from becoming lopsided.
Signs your geranium isn’t getting enough light:
- Leggy growth (long, weak stems)
- Fewer flowers or no flowers
- Pale green or yellowing leaves
If you don’t have access to a sufficiently bright window, consider supplementing with a grow light. Full-spectrum LED grow lights are energy-efficient and provide the light spectrum plants need to grow and flower. You can find excellent resources on choosing the right grow lights from institutions like the University of Wisconsin-Madison Division of Extension, which offers detailed information on plant lighting.
2. Watering: Finding the Sweet Spot
Overwatering is one of the most common mistakes beginner indoor gardeners make, and geraniums are susceptible to root rot if their soil stays too wet. The key is to let the soil dry out slightly between waterings.
How to water:
- Check the soil: Stick your finger about an inch into the soil. If it feels dry, it’s time to water. If it feels moist, wait a few more days.
- Water thoroughly: When you do water, water until you see it drain from the bottom of the pot. This ensures that all the roots get moisture.
- Discard excess water: Never let your geranium sit in a saucer full of water. Empty the saucer about 30 minutes after watering to prevent waterlogged roots.
The frequency of watering will depend on several factors, including the humidity in your home, the size of the pot, and the amount of light the plant receives. In brighter, warmer conditions, you’ll water more often than in cooler, dimmer conditions. It’s always better to underwater slightly than to overwater.
3. Soil and Potting: A Foundation for Health
Geraniums prefer well-draining soil. A good quality potting mix that includes perlite or vermiculite will help provide aeration and prevent waterlogging. Avoid using heavy garden soil, which can compact and hinder drainage.
Potting tips:
- Drainage Holes: Crucial! Always use pots that have drainage holes at the bottom.
- Pot Size: Geraniums don’t mind being slightly root-bound, so they don’t need huge pots. Too large a pot can hold too much moisture. A pot that’s 2-4 inches larger in diameter than the root ball is usually sufficient.
- Repotting: Repot every 1-2 years, or when the plant becomes root-bound. Spring is the best time to repot.
You can easily create your own well-draining mix by combining two parts of a standard potting mix with one part perlite or coarse sand. This is a simple and effective way to ensure your geraniums have the airy, well-draining environment they crave, mimicking the conditions they’d find in their native Mediterranean habitats.
4. Temperature and Humidity: Creating a Comfy Climate
Geraniums are quite adaptable to average home temperatures. They thrive in conditions between 60-70°F (15-21°C) during the day and slightly cooler at night, around 50-55°F (10-13°C). This slight temperature drop at night can encourage blooming.
Avoiding drafts: Keep your geraniums away from cold drafts, such as those from leaky windows or doors in winter, and also away from direct blasts of hot air from heating vents. These extremes can stress the plant.
Humidity is generally not a major concern for most geranium varieties indoors, as typical home humidity levels are usually adequate. However, if your home is extremely dry, especially during winter months when heating systems are running constantly, you might notice leaf tips beginning to brown. In such cases, grouping plants together or using a pebble tray filled with water (ensuring the pot sits on pebbles above the water line) can help increase local humidity. Avoid misting the leaves directly, as this can promote fungal diseases.
5. Feeding: Fueling the Blooms
To encourage abundant flowering, regular feeding is important, especially during the active growing season.
- When to Feed: Start feeding in early spring when you see new growth and continue through the summer and early fall. Reduce or stop feeding in late fall and winter when the plant’s growth naturally slows down.
- What to Use: A balanced, water-soluble fertilizer will work well. Look for one with a slightly higher phosphorus content (the middle number in the N-P-K ratio) to promote blooming. A formula like 15-30-15 or 20-20-20, diluted to half strength, is generally effective.
- How Often: Feed your geraniums every 2-4 weeks during the growing season. Always water the plant before fertilizing to prevent burning the roots.
For those interested in sustainable options, consider using diluted fish emulsion or compost tea. These organic fertilizers provide nutrients while also improving soil health over time. Always follow the dilution instructions on the product packaging, as over-fertilizing can be just as harmful as under-fertilizing.
Common Pests and Problems (and How to Solve Them!)
Even indoor plants can encounter a few challenges. Here are some common issues you might face with your geraniums and how to tackle them:
1. Aphids
What they look like: Tiny, pear-shaped insects, often green, red, black, or brown, clustered on new growth and the undersides of leaves.
What they do: They suck sap from the plant, causing distorted leaves and reduced vigor. They also excrete a sticky substance called honeydew, which can attract sooty mold.
Solution:
- Manual Removal: For small infestations, simply wash them off with a strong spray of water.
- Insecticidal Soap: A gentle option for larger infestations. You can buy it or make your own with a mild liquid soap and water. Ensure full coverage, especially under leaves. Repeat as needed.
- Neem Oil: An organic pesticide that disrupts insect growth.
2. Whiteflies
What they look like: Small, white, moth-like insects that fly up in a cloud when the plant is disturbed. They tend to gather on the undersides of leaves.
What they do: Like aphids, they feed on plant sap and can weaken the plant. They also produce honeydew.
Solution:
- Yellow Sticky Traps: These attract and trap adult whiteflies.
- Insecticidal Soap or Neem Oil: Effective against nymphs and adults. Frequent application may be necessary.
- Vacuuming: For a unique approach, a handheld vacuum can suck up adult whiteflies when they become airborne. Empty the vacuum immediately outside.
3. Thrips
What they look like: Tiny, slender insects, often black or yellow, that are difficult to see with the naked eye. They cause silvery or stippled damage on leaves and distorted flowers.
What they do: They scrape the surface of the leaves and flowers to feed on the plant juices, causing unsightly damage.
Solution:
- Pruning: Remove and discard any heavily infested leaves or flowers.
- Insecticidal Soap or Neem Oil: Effective, but repeated applications are often needed.
- Beneficial Insects: For persistent problems, consider introducing beneficial insects like predatory mites, though this is often more practical for larger collections.
4. Root Rot
What it looks like: Leaves turn yellow and may droop, despite the soil being consistently wet. The base of the stem might appear mushy or brown.
What it does: Caused by overwatering and poor drainage, this fungal disease attacks the roots, preventing the plant from absorbing water and nutrients.
Solution:
- Improve Drainage: Ensure your pot has drainage holes and isn’t sitting in standing water.
- Adjust Watering: Let the soil dry out significantly before watering again.
- Repotting: If severe, you may need to unpot the plant, remove as much of the soggy soil as possible, trim away any rotten roots (they’ll be black and mushy), and repot in fresh, well-draining soil.
5. Leggy Growth and Lack of Blooms
What it looks like: Long, stretched-out stems with few leaves; sparse or nonexistent flowers.
What it means: Usually a sign of insufficient light. It can also be caused by over-fertilizing with nitrogen, which promotes leaf growth over blooms, or the plant simply needing a prune.
Solution:
- Increase Light: Move to a brighter location or supplement with a grow light.
- Prune: Pinch back leggy stems to encourage bushier growth and more flowering points. Make cuts just above a leaf node.
- Fertilize Appropriately: Use a balanced or bloom-boosting fertilizer and avoid high-nitrogen formulas during flowering season.
Pruning and Deadheading for Continuous Blooms
Regular pruning and deadheading are essential for keeping your indoor geraniums looking their best and encouraging them to produce more flowers. These simple tasks don’t just maintain their shape; they signal the plant to focus its energy on new growth and blooms.
Deadheading: The Key to More Flowers
Deadheading involves removing spent flowers. Old blooms not only look unsightly but also divert the plant’s energy away from producing new ones. Follow these steps:
- Locate Spent Blooms: Look for flower stalks where the flowers have faded, turned brown, and started to wilt.
- Pinch or Cut: Gently pinch off the entire spent flower stalk by pulling it away from the main stem. Sometimes, you might need to use clean scissors or pruning shears to cut the stalk back to its base, close to the main leaf stem.
- Repeat Regularly: Make it a habit to deadhead your geraniums whenever you see spent blooms. This consistent care will reward you with a continuous display of fresh flowers.
Pruning: Shaping and Encouraging Growth
Pruning helps maintain a compact, bushy shape and encourages new, stronger stems that will produce more flowers. It’s particularly important if your plant starts to get leggy or overgrows its pot.
- When to Prune: The best time for significant pruning is in the spring, just as new growth begins. However, you can pinch back leggy stems anytime to shape the plant.
- How to Prune: Use clean, sharp scissors or pruning shears. Look for stems that are growing too long, crossing other stems, or growing inwards. Cut these back to just above a leaf node (where a leaf attaches to the stem). This encourages branching from that point.
- Pinching the Tips: For young plants, pinching off the very tip of a stem encourages it to branch out, creating a fuller plant.
Don’t be afraid to prune! Geraniums are quite resilient and respond well to trimming. You can even prune them back quite hard in spring if they’ve become leggy or overgrown from the previous year. The cuttings can often be used to propagate new plants, making pruning a double win.
Overwintering Geraniums Indoors
Many gardeners bring their outdoor geraniums inside for the winter to save them from frost. This process involves preparing the plant for a less active period. Here’s how you can do it:
Preparing Your Geraniums for Indoor Wintering
- Inspect for Pests: Before bringing any plant indoors, thoroughly inspect it for pests. Treat any infestations before they enter your home and spread to other plants.
- Trim Back: Prune the plant back by about one-third to one-half. This reduces its size, making it easier to manage indoors, and encourages a bushier plant come spring. Remove any dead or yellowing leaves.
- Repot (Optional): If the plant is severely root-bound or the soil is in poor condition, consider repotting it into slightly smaller pots with fresh potting mix. This helps reduce water retention and promotes healthier roots during dormancy.
- Gradual Acclimation: If possible, gradually acclimate your geraniums to indoor conditions over a week or two. Move them from full sun to partial shade, then to an indoor location. This helps prevent transplant shock.
Winter Care for Overwintered Geraniums
Once indoors, these plants will enter a period of semi-dormancy.
- Light: Place them in the brightest window possible. If light is limited, they may not bloom, and that’s okay.
- Watering: Reduce watering significantly. Water only when the top inch or two of soil feels dry. The goal is to keep the soil barely moist, not wet. Overwatering is the biggest killer of overwintered geraniums.
