Renewing an Overgrown Houseplant
When a plant like outgrows its pot, the roots get crowded and can't convey sufficient nutrients and moisture to the foliage. The plant becomes leggy, refuses to bloom, and may even start to lose its leaves. In short, it needs a new home. Not only will a bigger pot provide more space for the roots to grow, but it will hold more soil, and that means more water and nutrients will be available to the plant.
Byron Martin, owner of Logee's Greenhouses in Danielson, Connecticut, repots hundreds of plants each year. “One thing you want to remember when repotting is not to use a pot that's too big,” says Martin. “Increase the pot diameter by two inches. Any more than that and you risk having too much soil soaking up too much water. The water then has nothing to absorb it, and root rot can set in.”
By following Martin's steps, you can expect your plant to revive in a few weeks; full regrowth may take several months.
1. Trim back the plant. Though it looks drastic, when a plant is this leggy you can trim it way back to jump-start new. lusher growth. Place pruning shears just above a node and snip. The best time to do this is when the plant comes out of its winter rest period, usually late February or early March. However, if you like the shape of your plant and the roots merely need more soil, there's no need to cut it back. Mature woody plants with a well-established framework also shouldn't need drastic pruning.
2. Remove the plant from its pot. Hold the plant so that your fingers are braced on the soil on either side of the stem. Turn the pot upside down and give it a few good raps on a hard surface (a wooden bench, for example). Knock firmly but not so hard you break the pot; the plant should slide right out. If it doesn't. the roots may have grown through the drainage hole and will need cutting back first. If the roots are drastically overgrown, you may have to break the pot.
3. Fill in with soil. Holding the plant by its stem, fill in the new pot with a little soil. Set the plant onto the soil and liberally scoop more soil around it. centering the plant as you fill around the sides. “Make sure you don't fill the soil level with the pot's edge,” cautions Martin. “You need to allow room to water.”
4. Firm soil and water. Firm the soil around the plant with your fingers, then knock the pot on a surface to settle the soil. Add more soil until it is about a half-inch above the base of the plant. Water the pot thoroughly enough that some drains out of the bottom. The soil will settle when you water it. Add more, if necessary, so that it ends up level with the base of the plant. As always, don't leave the plant standing in the water that runs through.
From Horticulture Magazine