Growing Avocado from Seed

Growing Avocado from Seed

I still remember the first time I tried to grow an avocado from seed. I was 22, living in a tiny studio, and I thought sticking toothpicks into a pit would somehow make me a legitimate plant parent. Spoiler: that first pit molded after two weeks because I forgot to change the water. But I tried again, and eventually, I got it right.

If you’ve ever eaten an avocado and thought “I could grow this,” you’re not wrong. It’s actually one of the easier seeds to sprout, even though getting it to look like an actual tree takes patience. I’m going to walk you through what I’ve learned from growing three avocado plants (one is still alive, which I consider a win).

The toothpick and water method

This is the classic approach, and honestly, it’s pretty satisfying to watch. You get to see the whole germination process happening right in front of you.

First, eat your avocado. Rinse off the pit completely because any leftover fruit will rot in the water. I learned this the hard way when my kitchen smelled like death for a week. Once it’s clean, figure out which end is which. The bottom is usually flatter and wider. That’s where the roots will come from. The top is more pointed, and that’s where the stem will eventually push through.

Take three or four toothpicks and stick them into the sides of the pit at a slight downward angle, spacing them evenly around the middle. You want them to act like little arms that will rest on the rim of your glass. The toothpicks should be strong enough to hold the pit suspended so that only the bottom inch or so sits in water.

Fill a glass with water and set the pit on top. The bottom third should be submerged, but not the whole thing. I use a clear glass because I like watching the roots grow, but any container works as long as it’s stable.

Now comes the part that tests your patience. Put the glass somewhere warm with indirect light. I keep mine on my kitchen counter away from the window. Change the water every few days. This is important. Stagnant water gets gross and can kill your seed before it even sprouts.

It usually takes anywhere from two to eight weeks for something to happen. Sometimes the pit will crack open at the top first. Sometimes the root will push out from the bottom. According to research from the University of California Agriculture and Natural Resources, the germination time depends on the avocado variety and how fresh the seed is. I’ve had pits sprout in three weeks and others take almost two months.

Once you see a root that’s about three inches long and a stem pushing up from the top, you can either keep it in water longer or move it to soil. I usually wait until the stem has a few leaves before planting.

Planting the pit in soil

You can skip the water method entirely and plant directly in soil if you want. I’ve done this with a few pits, and it works, but you don’t get the visual satisfaction of watching the germination process.

Whether you’re transplanting from water or starting fresh, the process is similar. Get a pot with drainage holes. This is not optional. Avocado roots hate sitting in soggy soil, and they will rot if the water can’t escape. I use a pot that’s about 8 to 10 inches in diameter to start.

For soil, use a regular potting mix. Nothing fancy. I’ve read recommendations from horticulturists at Texas A&M University that avocados prefer well-draining soil with a slightly acidic pH, but honestly, standard potting soil from the hardware store has worked fine for me.

When you plant the pit, don’t bury it completely. The top half should stick out above the soil line. If you bury it too deep, the stem might rot before it breaks through. I made this mistake with my second attempt and wondered why nothing was happening for months.

Water it thoroughly after planting, then let the top inch or two of soil dry out before watering again. Avocados don’t like to be constantly wet. I stick my finger in the soil to check. If it feels damp, I wait.

Place the pot somewhere with bright, indirect light. A spot near a south or west-facing window works well. My apartment doesn’t get great light, so I supplement with a grow light during winter. Without enough light, the plant gets leggy and weak.

One thing I wish someone had told me earlier is that avocado plants are sensitive to salts and chlorine in tap water. If your water is heavily treated, let it sit out overnight before using it, or switch to filtered water. I started doing this after noticing brown tips on the leaves, and it made a difference.

Above: A close up look at the symptoms.

Pruning for a bushy tree

This is where most people (including past me) mess up. If you don’t prune your avocado plant, it will grow straight up like a stick with a few leaves at the top. It looks ridiculous. I had one that was nearly four feet tall with exactly six leaves clustered at the very top. It looked like a sad palm tree.

The first major pruning should happen when your plant is about 12 inches tall. Cut it back to about 6 inches. I know this feels brutal. You’ve spent weeks or months growing this thing, and now you’re chopping it in half. But it works.

When you cut the stem, the plant responds by sending out new growth from lower on the stem. Instead of one tall shoot, you’ll get multiple branches. This creates a fuller, bushier shape.

After that first big cut, you’ll need to keep pinching back new growth. Every time a branch gets about 6 inches long, pinch off the top inch or two. This encourages the plant to branch out instead of just growing taller. I do this every few weeks during the growing season.

Use clean scissors or pruning shears. I wipe mine down with rubbing alcohol between cuts. According to plant pathology research from Cornell University, this helps prevent spreading diseases between plants.

I’ll be honest, I’m not great about remembering to prune regularly. My current avocado plant is more tree-like than bushy because I got lazy. But the difference between a pruned and unpruned plant is night and day if you actually follow through.

Patience: Growth timeline

Here’s the reality check. Growing an avocado from seed is a long game. If you’re hoping for fruit, you need to know that seed-grown avocados can take anywhere from 5 to 13 years to produce fruit. And even then, the fruit might not taste like the avocado you originally ate because avocados don’t grow true from seed.

I’m not growing mine for fruit. I just like having a weird plant project that costs nothing except time.

In the first year, if everything goes well, you might get a plant that’s 1 to 2 feet tall with a handful of leaves. Growth is faster in spring and summer when the days are longer and warmer. In winter, my plant basically stalls out and doesn’t do much of anything.

The leaves grow in flushes. You’ll see new growth appear, then nothing for a while, then another round of new leaves. It’s not steady like some houseplants.

Research from the University of Florida IFAS Extension notes that avocado seedlings need warm temperatures to thrive. They really struggle below 50 degrees Fahrenheit. I learned this when I left mine outside during an unexpectedly cold September night and it dropped half its leaves.

The other thing about the timeline is that avocado plants go through phases where they look terrible before they look good again. The lower leaves will yellow and drop as the plant matures. This is normal. It freaked me out the first time, but it’s just the plant shedding older growth.

If you’re growing this indoors as a houseplant, it will probably never get huge. Mine has maxed out at about 3 feet in a pot. Outdoors in the right climate, these things become actual trees. But in my apartment, it’s just a conversation starter.

Above: The tools you need to fix this.

Why leaves turn brown

Brown leaves are basically guaranteed at some point, and there are about five different reasons it might be happening.

The most common cause is underwatering. Avocado plants are sensitive to drought stress. If the soil gets too dry, the leaf tips and edges turn brown and crispy. I’ve done this more times than I care to admit because I forget to check the soil for a week.

But overwatering causes brown leaves too, usually accompanied by yellowing. If the soil stays soggy, the roots can’t breathe, and they start to rot. The leaves respond by turning brown and mushy rather than crispy. This is harder to fix than underwatering.

Salt buildup is another culprit. This happens from using tap water with high mineral content or from over-fertilizing. The salts accumulate in the soil and damage the roots, which shows up as brown leaf tips. Flushing the soil with distilled water can help, or you can repot with fresh soil.

Low humidity can also cause browning, especially in winter when the heat is running. Avocado plants prefer higher humidity than most homes provide. I’ve tried misting mine, but honestly, it didn’t make much difference. A humidifier works better if you’re serious about it.

Lastly, cold drafts will turn leaves brown overnight. Don’t put your plant near a drafty window in winter or directly under an air conditioning vent in summer. I killed a lot of leaves by having mine too close to my window AC unit.

According to agricultural extension research from UC Davis, avocado plants are also sensitive to certain nutrient deficiencies. Brown leaves with yellow veins can indicate iron deficiency, while brown tips might signal a lack of potassium. I don’t fertilize mine often, maybe once in spring and once in summer with a diluted houseplant fertilizer, and that seems sufficient.

The truth is, your avocado plant will probably always have a few brown leaves. I’ve never seen one that looks perfect. But as long as it keeps putting out new growth, it’s doing fine.

Growing an avocado from seed won’t give you guacamole anytime soon, but it’s a fun, cheap way to add some green to your space. Mine has survived two apartments, one cat who tried to eat it, and my general forgetfulness. If it can make it through that, yours probably will too.

References

University of California Agriculture and Natural Resources. “Avocados: Safe Methods to Detect Ripeness.” ANR Catalog.

Texas A&M AgriLife Extension. “Avocado.” Earth-Kind Landscaping.

Cornell University Department of Plant Pathology. “Sterilizing Pruning Tools.” Plant Disease Diagnostic Clinic Resources.

University of Florida IFAS Extension. “The Avocado.” Horticultural Sciences Department.

University of California, Davis. “Diagnosing Nutrient Deficiencies.” UC Davis Cooperative Extension.