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Last Updated on January 29, 2023
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It’s not as tough as you may imagine to cultivate avocados in an indoor environment. All you need is a little patience and the right conditions. Avocados (Persea americana) are tropical broadleaf evergreen trees, bearing green fruit and can grow up to 80 feet tall.
In native conditions, they require warm temperatures, a certain amount of humidity, and plenty of space to thrive. On the surface, in terms of shape and size, and growing conditions, avocado trees don’t appear to be the sort of plant that you can grow indoors at home.
However, With a little bit of care and good growth control management, you can create the perfect environment to successfully grow an avocado tree indoors. In this article, we will look at how you can grow from seed or cutting an avocado houseplant that will fit and thrive inside your home
Growing Avocados from Seed or Young Trees Indoors
There are two options for growing the trees indoors. You can either grow from seed or you can start with a young juvenile tree. The option you choose will largely depend on whether you are keen to manage the whole growing process or whether you are looking for an established plant for decorative purposes.
Possibly the most common of these is Hass, which is the variety whose fruit is predominantly seen on supermarket shelves. Just taking the seed from a shop-bought avocado will generally germinate and the Hass variety will grow well indoors. There are though, a considerable number of varieties of avocados, and some like Wurtz, a dwarf variety of tree, are better suited to into growing because eventual size is limited to around 8 feet. These you can find at many nurseries either as seeds or juvenile trees.
How to Grow Avocado From Seed
Avocado plants are not too difficult to grow. A warm sunny window and a few sundry items are all you need to successfully grow your avocado tree.
What You Need:
- Avocado seed (avocado pit)
- Growing medium
- Pot and drainage dish
- Support sticks (for growing in water)
- A window with at least five to six hours of sunlight a day
Procedure in Soil or Dirt-Based Growing Medium
- Fill your pot with around six inches of growing medium
- Determine the top of the seed usually, the thinnest point but also the end at the top of the fruit when cut open
- Place the seed in an upright position in the soil with the top pointing up
- Fill around the seed barely covering the top of the seed (some leave the very top slightly uncovered)
- Water and place in warm direct sunlight, ideally in front of a window
Procedure for Growing Avocado in Water
- Fill the container with warm water
- Determine the top of the seed usually, the thinnest point but also the end at the top of the fruit when cut open
- Pierce the seed with three or four support slanting slightly down (cocktail sticks/toothpicks work well)
- Place the support stick on the top of the jar or container filled with water
- The bottom part of the seed should be submerged in water, the top half should remain dry
- Place in a warm spot with direct sunlight, ideally in front of a south-facing window
How Long Does It Take to Germinate
If you the planting from seed you should start to see the avocado seed germinate and sprout within a couple of weeks, although, depending on light and other environmental conditions, can take up to six weeks. Once the tree has germinated, the now avocado seedling will begin to grow quite fast and within 1-2 months, it should be 12 to 18 inches tall.
If growing in water, growth should follow roughly the same time span. You will see good root growth in two to four weeks (again environmental conditions could make this longer) and top growth of 12- 18 inches in a further couple of months.
You should notice that the tap root has grown longer than the other avocado roots and possibly begun to branch. Once at this point of being a seedling, you can transfer the tree to a pot.
When your plant has grown to around twelve inches tall, take a deep breath and cut it back six inches or so, to a place a little above a growth node (this is just above a leaf growth). It is not essential that you do this but it will help strengthen the stem of the plant and make it stronger.
Propagating Avocado from An Existing Branch
As well as from seed you can also propagate avocado trees from the branch of an existing mature tree, and again is quite easy to do. You need to take the cutting in the early spring when it is about to begin its growth cycle. Make sure when taking the cutting you cut diagonally across the stem giving you a length of the branch about six inches long.
Preparing to Plant the Cutting
- Take your cutting and dispense with all the leaves around the bottom third.
- Then pare back the skin on two sides above the cut about half an inch long.
- Coat this area in indole butyric acid. This will help encourage root growth.
- Prepare a growing medium, peat moss, a citrus potting mix, or even loam soil, and push the bottom third into the dirt.
- Water the growing medium
- Cover the cutting with a clear plastic bag, this will help generate humidity
- Place on a warm window sill that gets a good amount of sunlight daily
- Monitor the cutting for four to five weeks, then if necessary repot in a larger pot
- Fertilize the cutting every month as it grows but at it matures reduce down to two to three times a year
From Avocado Seedling to Sapling
When your tree reaches around four feet from the ground your seedling has become an avocado sapling. The trunk will by this point be around one to one and a half inches in diameter. Your tree should reach this stage in around twelve to eighteen months. It is at this point that you can think about whether to keep the tree as an indoor plant or contemplate planting it outside.
Maintaining Your Tree – Indoor Avocado Tree Care
Once you have got your seedling growing it is important to maintain it properly to keep it healthy and allow it to thrive. This involves making sure the indoor environmental conditions are right and that you feed, water, and prune it correctly.
As we have mentioned, the trees like warm humid conditions with plenty of direct sunlight per day in order to grow well. It should not be too difficult to find a nice sunny spot particularly if you have south or west-facing windows. However, it is unlikely that you want any room to be too humid, although, the trees perform better in humid rather than dry conditions. It could be useful to check humidity levels to make sure the atmosphere is not too dry.
Fertilizing Your Tree
Beyond making sure your plant is getting enough sunlight per day Your plant is going to need the correct nutrients in order to prosper. With young plants indoors you will need to look to fertilize every month. With mature trees, you would fertilize two to three times a year generally in spring and fall but before the plant goes dormant for winter.
In terms of fertilizer, you should use one with a nitrogen, phosphorous, and potassium (NPK) ratio of 6-3-3 or 2-1-1 the choice being the amount of nitrogen you need to add in a given application. With young plants, you need to be careful with the amount of nitrogen given. Not enough can inhibit growth while too much can burn the roots. Depending on age, an avocado tree can require between half and one and a half pounds of nitrogen each year so fertilizing on a regular schedule is important.
Avocado plants like and grow better with good amounts of the micronutrients boron, zinc, and magnesium. Look for fertilizers with these included or add them as amendments.
You can use either liquid or granular fertilizer but granular allows the slow release of its nutrients which will benefit the growth of the tree. You can use organic materials like compost but you may need to add nitrogen.
In terms of soil, the trees prefer slightly acidic soil with a pH of between 6.0-7.0.
Watering and Drainage
In addition, avocado trees require a reasonable amount of water with fully grown trees needing around two inches each week. You will therefore probably need to water your trees two or three times a week to provide them with enough moisture to thrive and grow.
There are however several important things to know when watering. The plants have a shallow root structure and are susceptible to root rot. It is important to have good soil structure, your pot to have adequate drainage holes, and to monitor soil moisture levels to avoid problems.
When watering you should look to water deeply around once a week or more if you see the leaves appear to wilt.
Pruning is incredibly important if you are looking to grow an avocado plant indoors. It is the way that you can manage the growth of the plant so that it fits inside your house comfortably.
Avacado trees can grow several feet a year. They grow quickest in their earliest years and this is the formative stage of their growth. You can aggressively prune the tree to keep it to a maximum height. You will need to do this each year to maintain a height of six to seven feet which should fit into most homes.
You also have to stunt the spread or the tree will grow outwards. You can stunt the spread of your tree by pinching. This involves removing the tree’s buds, to prevent it from branching.
Fungus Growth and Insects
Avocado trees are suspectable to fungus growth and insect attack which cause the leaves to either develop brown spots or cause browning around the edges.
The most common fungal diseases are
Anthracano –Symptoms: develops brown spots and causes the leaves to wither and die. Treatment: Remove infected leaves, check container and soil for signs of overwatering, and use fungicide on the affected area.
Septoria leaf spot – Symptoms: Lots of small brown spots on the underneath of the leaves. Treatment: Remove infected leaves and treat with a copper-based fungicide
Alternaria leaf blight – Symptoms: Affect mature leaves and takes the appearance of small brown spots with a yellowish border. Treatment: Reduce or cease watering completely and treat the tree with copper-based fungicide each week. Prune back the tree and add com organic material such as compost to the soil.
Will Indoor Avacardo Trees Bear Fruit
The fact that an avocado tree is indoors or outdoors is irrelevant as to its fruit-bearing capacity. What matters is the environmental conditions it is kept in and it proximity to other trees. It is perfectly possible for your indoor avocado tree to bear fruit, although whether it does and the extent of the yield will depend on a number of factors from age, to the type of avocado tree, to temperature, and pollination methods.
The first factor is pollination. Avocado trees are unusual in that, unlike other fruit trees, they are not self-fertile. This is due to their unusual flowering cycle which ensures that only either all male or all female flowers are available at any single time. They need external actors such as insects to cross-pollinate between trees that have different sex of flower open at the same time.
By implication, this means that nature requires that more than one tree is needed to pollinate the flowers to enable the tree to fruit. In an indoor setting, you would need plenty of space for two trees.
What complicates the issue, even more, is that you are likely to need two different types of avocado trees to ensure effective pollination. This is because the various varieties of avocado plant are split into two distinct types, Type A and Type B. The difference between these types is their flowering sequence synchronization, one being opposite to the other.
However, all is not lost. If you want your indoor avocado tree to bear fruit then nature can be overridden through hand pollination, a simple process whereby you manually pollinate the flowers on your tree. You can read more about how to hand pollinate here.
The second factor is that of age. An avocado tree will not bear fruit until it is mature enough. If your tree is grown from seed this is likely to be around ten years. If on the other hand, you have bought a juvenile tree from a nursery, then fruiting is possible earlier. Sometimes this can be in as little as three years, but more generally in five to six years.
The acceleration is due to the fact that the trees sold in nurseries are propagated from mature trees, rather than grown from seed. However, the tree must be physically strong enough to bear fruit. On younger trees, the fruit will fall before it is fully developed.
Relationship Between Climate Conditions And Fruit Yield
A third factor that determines whether a tree fruits is climate. As we have mentioned avocado trees are native to tropical regions which means they perform best in warm humid climates, where temperatures do not fluctuate much between day and night.
Clearly, you are unlikely to want warm humid conditions in your room, but a stable warmish temperature is something that you are likely to want. Fortunately, avocado plants are versatile in that, provided it is not too cold, they will grow just fine. With average room temperatures around the 65°F mark, pretty much most varieties will grow well. For example, the Hass variety we discussed as the most common enjoys temperatures between 60°-80°F.
If however, you plan to move the tree outdoors when it reaches a certain size, then you have to be aware of the cold tolerances in the winter months. Some varieties are better than others at coping with colder temperatures.
Keeping Up Maintenance
Of course, no plant will thrive without proper care and Avocados are no exception. Although a relatively easy tree to grow it does require the right nutrients being present. As you are growing the tree in a pot the amount that can be provided from the soil or growing medium will be limited. This means that you need to monitor the nutrient levels. An avocado tree can require between half and one and a half pounds of nitrogen each year so fertilizing on a regular schedule is important.
In addition, avocado trees require a reasonable amount of water with fully grown trees needing around two inches each week. You will therefore need to water your trees a least once or twice a week using a deep soak method to provide enough moisture for them to stay healthy.
Summary; How to Grow Avocado Indoors
When you can’t grow outdoor avocado trees, growing an avocado plant indoors is an alternative option. As we have seen it is not particularly difficult and they make excellent indoor plants. in addition, with the correct environmental conditions and a bit of patience and planning, you should also be able to produce avocado fruit.
You can use a seed or propagate from a cutting to grow your indoor avocado plant with the main requirements being plenty of sunlight and a warm environment. Or you can purchase a sapling from your local nursery making it a very accessible plant.