Why Tips Turn BrownPlants naturally use and lose water through their tissues each day. Leaf tips turn brown when that lost water can't be replaced for some reason. Ideally, water flows from plant roots through stems and waterways until it finally reaches leaf tips last. But when water's limited, other plant parts get served first; tip cells lose out and die from a kind of drought.
Anything that inhibits roots from absorbing enough water — or supplying it to the plant fast enough — can lead to unsightly brown tips. This includes providing the plant with too much water, too little water or too much fertilizer. Root damage or distress also prevents roots from doing their job.
Though specific factors can differ between protected indoor plants and plants exposed in landscapes outdoors, brown tips arise for the same basic reasons. Once they turn brown, those dead tip cells can't be revived, but quick corrections help restore the rest of your plant to health.
Troubleshooting Brown Leaf TipsEven though brown leaf tips look dry and thirsty, don't be deceived! Water may be the last thing your plant needs. Simple botanical detective work helps get to the root of the problem. Just take the following steps:
1. Get a firsthand look at what's underground.
Seeing what's happening with struggling roots helps diagnose the problem. This is easier with potted plants than with in-ground, landscape plants, but there's no substitute for an up-close look below.
Coax brown-tipped houseplants out of their pots by turning them on their side and gently pulling the plant by its base. Most plants come out easily. If yours sticks, gently work it loose. Don't be concerned about hurting your plant; professional growers frequently take this same step.
For landscape plants, don't dig up the entire plant. Focus on a single area instead. Start with a spot between the plant's main stem or trunk and the outer edge of its leaf canopy, where rain drips down to the ground. Then dig a hole 6 to 12 inches deep to get a good peek at what's happening in soil. For larger plants, dig more than one hole to see if any problems look widespread.
Whether safely tucked in a living room corner or exposed to outdoor elements, the soil around plants should generally be cool and moist to the touch. Unless you're growing aquatic plants or marshland natives, plants should never be sitting in water. Roots need air, whether they live in pots or in the ground. In soggy soil, drowning roots shut down and rot, and new roots can't form. Without healthy roots to absorb and transport water, plant tips turn brown from thirst.
When a houseplant is pulled from a pot, the soil around the roots should hold its shape and not drip water. If the soil is overly wet, check for blocked drainage holes and clear them to be sure water runs through. Adjust your watering schedule accordingly to be sure you're not watering too much.
If houseplant soil falls apart or holds a hard, dry shape, water hasn't been getting where it's needed. Soil can form a hard crust or pull away from the sides of pots, until water runs down the sides and misses roots completely. Break up any crust, and press the soil back against the pot's side to keep water headed for roots.
These same principles apply to landscape plants. If your soil is overly wet throughout the planting area, either you or nature overwatered or your soil is poorly drained. If your soil is hard, crusty or extra dry, you haven't watered enough or your soil drains too quickly.
To check landscape drainage, dig a hole 12 inches deep and fill it to the brim. Let it drain completely, then immediately fill it with 12 inches of water again. Measure the depth of the water at 15-minute intervals to discover how much water drains per hour. If less than 1 inch drains per hour, your soil stays far too wet. One to 6 inches per hour is good, but more than 6 inches in an hour means water slips away too fast, before your plants get all they need.1
Soil testing can help determine if your planting area needs soil amendments, such as Lilly Miller Garden Gypsum to loosen compacted clay soils and improve water and root penetration or earthworm castings to increase organic matter and improve the soil's capacity to hold water and nutrients. Soil testing is always a good idea before planting new outdoor areas.
3. Take a close look at roots.
Roots provide clues to their physical health and their surrounding environment. Healthy roots, with a few colorful exceptions, are white and firm with a fresh, soil-like smell. Gray or brown roots are usually dead or dying from too much water — and the opportunistic diseases soggy soil invites — and they smell like rot.
Roots that wind back upon or around themselves also signal trouble for potted or landscape plants. These circling or binding roots create a condition known as being “root bound." This happens frequently in containers that plants outgrow or that weren't large enough at planting time.
Roots on established potted plants should extend out to where the soil meets the pot, but never wrap around extensively inside. If pots become bound in roots, remaining soil can't hold enough water to meet the need. Repot root-bound plants into larger containers, but gently loosen the roots with your hand before you pot. This way, roots can grow out into the new soil.
Landscape plants usually don't have problems with binding roots, unless the problem was there at planting time or soil conditions prevent normal, natural growth. Soil testing and appropriate amendments, paired with a firm, gentle hand to loosen any binding roots before planting, keeps this problem out of your landscape.
4. Scout for signs of fertilizer residue or salt buildup.
Plant tips can turn brown when they're exposed to too much fertilizer and too many salts build up in the soil. When this happens to potted plants, tips turn brown from a condition known as fertilizer burn or tip burn. In landscape plants, the same thing happens from too much fertilizer or other factors such as winter deicing salts or pet urine. Indoors or out, soluble salts build up in soil, draw moisture away from plant roots and create an artificial drought. As a result, water-deprived plant tips turn brown.
In houseplants, salt buildup shows up as white crust on soil or saucers and on the sides of porous pots. Flushing the soil with heavy doses of water forces salts out and restores normal balance around roots. Just sit the pot in the sink or tub, and water it until the soil is soaked and water runs through. Repeat the process several times to flush the soil thoroughly.
If landscape plants are exposed to over-fertilizing, road salts or heavy pet use, don't wait for tips to turn brown. Water plants heavily and repeatedly to flush out the soil and prevent tip burn. The heavy watering leaches away built-up salts. If plants start to show brown tips as soil thaws in spring, they may have been exposed over winter. Flush the soil through heavy watering right away.
Avoid fertilizer burn by feeding plants with a non-burning fertilizer, such as Alaska 5-1-1, for gentle, health-boosting nutrients without harmful buildup.
5. Keep recovering plants on track.
Once your plants are back on the path to good health, adjust your care — especially watering — to keep them headed in the right direction. Never water automatically, whether plants are potted or in the ground. Test the soil manually first, by feeling it at an index finger's depth. If it feels wet, wait a few days and check again. If soil feels dry, it's time to water. If you use tap water to water your indoor plants, let water sit overnight. This reduces fluoride and other substances that can add to brown tips.
Most plants stay healthiest when watered deeply and infrequently, in your home and your landscape. Water houseplants so all the soil is moist, then let them dry slightly before watering again. If the humidity in your home is very low, a pebble-filled saucer at the plant's base can help keep tips and moisture in balance.
During active periods of growth, most outdoor plants need the equivalent of at least one inch of rainfall each week, including natural precipitation. When watering, this equals about 5 gallons of water per square yard. Most roots, even on large landscape trees, stay in the top 6 to 12 inches of soil. One inch of water seeps down to that depth in most soils, keeping healthy roots supplied and leaf tips well-hydrated.1
6. Get rid of the evidence.
With your care regimen on track and plants on their way to good health, you don't need brown tips to remind you of the past. Landscape plants will take care of the problem as the seasons pass, but potted indoor plants can use a hand.
Take a cue from professional interiorscapers — the folks who care for indoor plants in offices and malls — and put brown tips behind you. Use sharp scissors to cut away the dead, brown areas. Just follow the leaf's natural shape. You'll still have a thin brown line along the cut, but the rest of the leaf will stay green and healthy as your plant moves ahead.
With a little investigation, appropriate corrections and proper ongoing care, your plants can trade brown-tipped leaves for strong, healthy ones. With the help of the Pennington family of plant care products, you and your plants can get back on the path of good plant health and natural beauty.
Alaska is a registered trademark of Central Garden & Pet Company. Pennington is a registered trademark of Pennington Seed, Inc.
1. Cornell University Department of Horticulture, “Soil Basics," Cornell University.
2. Weicherding, Patrick, "Watering Trees," University of Minnesota.
Topics: Indoor Gardening, Gardening