The first year we had our kaffir lime tree, it only bore one fruit and the few flowers that were on the tree had fallen off. I was worried that there was something wrong with it, so I did some research to find out how to fix it. Here’s what I found.
Citrus trees won’t flower properly if they aren’t yet mature or if they’re highly stressed. It usually takes citrus trees between 2-7 years to mature, depending on if they’re grown from seed or grafted. Stressors can include climate, watering, nutrients, pests, and disease.
While there are a few reasons that make each citrus tree slightly different, there are some similarities that we can use to induce flowering for your trees.
Here’s what we’ll cover in the rest of this article:
- Why some citrus trees don’t flower
- How to encourage your citrus trees to flower
- When citrus trees flower
- What to do if your citrus flowers are falling off
Let’s get into it!
The Top 3 Reasons Why Your Citrus Tree Isn’t Flowering
Several factors contribute to how your citrus trees flower, and fortunately, most of them are in your control.
For a citrus tree to have abundant and healthy flowers, the tree should be at a mature age of 2-7 years, have adequate watering, and have quality nutrients. The maturity of the tree will depend on how it was grown. Citrus trees grown from seed typically mature in 2-7 years, while grafted trees can mature in 2-3 years.
Let’s take a further look at these factors and what we can do to influence them and get our citrus trees to bloom.
1. Different Varieties of Citrus Trees Bloom Differently
As mentioned above, most citrus trees bloom in the springtime. However, different varieties of citrus bloom differently. Knowing your specific tree’s blooming patterns is an important first step.
Next, find out how long you’ve had your tree. Most citrus trees take several years (even up to 15 years) to begin growing fruit, especially those grown from seed. In fact, many lemon and lime trees take 3 to 5 years to begin blooming, while an orange or grapefruit tree might not see its first fruit for 10-15 years.
On the other hand, grafted citrus trees fruit in as little as 2-3 years. This is due to the grafting process of taking a scion from a mature tree and attaching it to a rootstock of a younger tree (usually a variety of orange tree). By using the more mature DNA from the scion, your tree will fruit much faster.
Another benefit of grafting is that the fruit is usually true to seed, which is important for many growers. This means there’s a strong likelihood that the fruit is similar to the original tree, and won’t be genetically different in appearance or taste (which often happens when growing from seed).
If you’re hoping for robust and thriving citrus trees, you might be in for a bit of a wait before the full effect of flowers and fruit begin to show. Consider purchasing citrus trees that are grafted, or grafting your own if possible.
2. Improper Watering or Fertilizing
As you probably have guessed, citrus trees need proper watering and fertilization to grow and flower properly.
In general, water your trees once every 1-2 weeks, and fertilize them every 1-2 months if you’re using a store-bought fertilizer, and once every growing season if you’re using a homemade fertilizer or compost.
The best way to water citrus trees is with deep watering. Along with the information I gathered from our citrus trees in our garden, I did a few more hours of research and put together a guide to deep watering.
For fertilizer, choose a brand that has twice the nitrogen to phosphorus and potassium (these three make the primary nutrients for most plants, abbreviated as “NPK”).
As an example, an NPK of 6-3-3 is a good choice to use for both planted and potted citrus trees. It will also have enough phosphorus to promote healthy blossoms (one of the most vital nutrients for flowers).
For more about fertilizers for potted citrus plants, check out my recommendations on the best citrus fertilizers you can buy. If you want something a little more natural, then check out my other post on making your own homemade citrus fertilizer.
3. It Has the Wrong Environment
Citrus trees love the sunshine and are not friends with cold weather. Just like people don’t function optimally if we are too hot or too cold, neither will a citrus tree. If your citrus tree isn’t flowering, take a look at its environment.
If your tree isn’t already in the sun, move it to an area that gets sunlight all day long. However, some climates can get extremely hot and can cause flowers to die and fall off. This is because the citrus tree, when stressed, will reserve water and sugars for the trunk and branches to ensure survival. The first things it will shed when stressed are leaves, flowers, and fruit.
So, if you need to provide your citrus trees with some protection from the sun, consider mulching the soil around the tree and providing afternoon shade if possible.
Mulching citrus trees will not only block the sun from baking the soil, but it will also increase water retention and keep more moisture in the ground. In most cases, cool roots will also help cool the tree.
On the other hand, if your tree is outdoors in cold weather, think about moving it inside next to a window that gets a lot of sunlight during the colder months.
If your citrus tree is planted outside, consider covering it with sheets or insulating it with cardboard in the winter months. Planting alongside a southern facing wall will also help reflect the heat from the sunny wall onto the plant most of the day.
Keep in mind that citrus trees don’t need fertilizer in the winter when they’re more dormant, so begin fertilizing again when the growing months arrive.
How to Encourage Your Citrus Tree to Flower
Paying attention to the suggestions below will encourage your citrus tree to flower. So, here are a couple of tips on how to encourage your citrus tree to flower:
- Patience is key. A watched pot won’t boil, but a watched citrus tree won’t automatically bloom either. Remember, trees need time to mature enough to flower. If you’re in a hurry, consider a smaller, grafted, variety of citrus. They often flower more quickly than a grapefruit tree for example.
- Fertilize when necessary. Fruit spikes or other fertilizers are great helpers to encourage quicker, fuller flowering of your citrus trees.
- Provide proper watering. The goal is to water citrus trees deeply to encourage better water retention and self-sufficiency during times of drought, but be careful of over-watering. Overwatering can quickly drown your tree roots and cause root rot. This is what I did to our kaffir lime tree (it survived after we repotted it).
- Keep your trees in the proper environment that isn’t too cold and ensures plenty of constant sunshine for optimal flowering.
While they are small, these actions will add up and result in a much higher likelihood that your citrus tree will flower.
When Do Citrus Trees Flower?
Since we have five different citrus trees, we put together some information for when we normally see them flower and bloom. Here’s what we found.
Most citrus trees flower in the springtime around March and April. However, some citrus trees can flower later in the year. Meyer lemons, grapefruit, and orange trees all have different flowering schedules ranging from late spring to early fall.
For example, some Meyer lemon trees can bloom all year, but they flower most abundantly in spring and sometimes fall. Many grapefruit trees flower later, in April and May.
Orange trees, likewise, begin their bloom just after the warmer months end like their citrus companions. However, there are orange trees and other citrus varieties that are considered early season, midseason, and late-season trees.
Be sure to do your research to know which type of tree you have so you are not looking for it to flower at the wrong time. For example, a late-season citrus tree does not like to be rushed to flower in the early season.
For more information about when citrus trees fruit, check out my other post on how long it takes citrus trees to fruit.
What Does a Flowering Citrus Tree Look Like?
The stages of flowering are similar for most varieties of citrus trees, but the months of the year that each of these stages occurs depends on the fruit.
Flowering on citrus trees occur four stages:
- Budding stage: In the budding stage, you will notice green buds begin to form. For lemons, this often occurs between November and January. When the buds begin to flatten in January, the flowering stage is soon to begin.
- Flowering stage: The buds blossom into five-petaled tiny white flowers, signaling the flowering stage. Bugs love these flowers, especially when they are clustered together. Insects often pollinate the flowers at this stage. After all, who could resist the sweet smell of citrus?
- Fruit set stage: The fruit set stage comes next. The flowers turn into citrus, and the citrus grows. This happens rather quickly throughout the season and depends on the citrus variety.
- Ripening stage: The final stage is ripening. Even a fully grown citrus fruit needs to continue ripening to be ready for picking and eating. The time it takes for the fruit to ripen varies. For lemons and limes, you might only have to wait a few months to have ready-to-eat fruit. For grapefruits and oranges, 12-18 months of waiting is a more practical timeframe.
What to Do if the Citrus Flowers Are Falling Off
Most citrus trees overproduce their flowers, to the point where the vast majority of them fall off. This is totally normal and is a way for citrus trees to maximize their pollination. However, if ALL of the flowers on your citrus tree are falling off, then something else could be going on.
When all the flowers fall off of a citrus tree, it usually signals that the tree is in distress. Here are a couple of reasons why it might be happening and a few remedies:
- Over or under-watering. Without enough water citrus trees go into drought stress and can lose their flowers. To remedy this, begin by lightly watering gradually and eventually get your citrus tree used to deep watering. Overwatering can also induce stress can cause the flowers to fall off. Check your citrus tree’s soil for moisture each day after watering. If the soil is sopping wet after two or more days, it’s time to water less or provide more drainage.
- Your tree might need a blanket. It’s true! A tree with consistent climate temperatures of under 35°F (1.7°C) might need to be kept warm with a frost blanket. If your tree flowers are falling off and you’ve made sure the tree is watered properly, keeping it warm is the next step.
- Your tree isn’t pollinating effectively. Most citrus trees are self-pollinating, however there are a few that require cross-pollination. For a list of different citrus trees and their pollination requirements, check out my other post.
To see how you can pollinate your citrus tree’s flowers by hand, check out this video by bearzhere.
While some citrus trees flower without any issues, if your tree isn’t flowering, it’s likely due to age or stress. For best results, get citrus trees that have been grafted and provide the proper watering, nutrition, and environment for them.
Keep in mind that while most citrus trees are self-pollinating, others require cross-pollination. What even more interesting is that self-pollinating citrus trees can still benefit from cross-pollination. So, if you have bees, hummingbirds, or butterflies, consider keeping them around and planting pollinator-friendly plants to increase their numbers. Doing so should help the number of flowers and fruit that develops on your citrus trees.