English ivy plants (Hedera helix) are not very tolerant of poor growing conditions. To nurse a dying ivy plant back to life, it's important to understand why it started to die in the first place. Inadequate light and humidity, improper watering and hot temperatures can cause an ivy houseplant to die. Once the issue is corrected, it should bounce back quickly.
Meet the Sunlight Requirements
English ivy makes a great indoor plant because it prefers partial shade. For best results, ivy needs to be exposed to bright light while simultaneously avoiding direct sunlight. Low light levels will stunt the plant's growth and lead to uniform coloring in variegated varieties. Situate your ivy plant in a window that faces north, east or west, and consider setting up an artificial grow light if these windows are excessively shaded.
Provide Adequate Humidity
English ivies tolerate the humidity level in a typical home, but they'll grow more vigorously and resist pest infestations if grown in moderate to high humidity. In addition, a dying ivy plant doesn't have the resources to tolerate less-than-ideal conditions, so raising humidity levels around the plant is a priority.
Find a shallow tray and fill it with several large stones, a layer of pebbles or a couple of bricks to support the ivy pot. Fill the tray with enough water to cover all but the top of the stones, pebbles or bricks. To keep the plant's roots from rotting, make sure the pot doesn't come into contact with the water in the tray.
Water will evaporate from the tray and increase humidity in the air immediately around the plant. Keep water in the tray at all times. Ivy plants also do well with good air circulation around their leaves, so prune out thick growth in the plant's interior.
Water English Ivy Correctly
English ivy will start to turn brown and die with both too much and too little water. With too much water, the roots stay soggy at all times and can't properly absorb oxygen (just as humans can't breathe oxygen underwater). The plant will die as a result. But too little water is just as problematic, since, among many other important functions, water is vital for transporting nutrients from the roots to the leaves.
A good rule of thumb is to allow the top half-inch to 1 inch of soil to dry out before thoroughly watering an ivy plant. With ivy, it's better to err on the side of underwatering rather than overwatering.
Keep Ivy Pests at Bay
If you feel like you're doing everything else right in terms of caring for your ivy plant, closely inspect the underside of its leaves and its stem for pests. Although pests are less likely to attack indoor plants, you may find aphids and spider mites, among others, on your English ivy. If you see them, take the plant outside and spray it with water from the hose, dunk it upside down in a bucket of soapy water or spray it with neem oil. If the pests have congregated on just one or two branches, prune them off.
A healthy, unstressed plant has some natural defenses against pests. You can ensure an indoor English ivy plant isn't stressed by keeping it in a cool area of the house, away from dry heat from furnace vents. According to Clemson Cooperative Extension, English ivy prefers daytime temperatures around 55 to 70 degrees Fahrenheit and nighttime temperatures about 10 degrees lower.
Proper nutrition is also important for boosting a plant's natural defenses. Ivy should be fed an indoor houseplant fertilizer once a month only when it's actively growing. Do not fertilize it in the heat of summer or the chill of winter, since ivies stop growing in both conditions.