Sarracenia pitchers turning brown: normal aging or trouble

Normal browning and the warning signs

Sarracenia lose pitchers all the time, and most browning is not a disease. Flora of North America describes the pitchers as marcescent or persistent, meaning dead pitchers often stay attached to the plant rather than dropping off ^[5]. Older pitchers die during the season while new ones grow, and in autumn the whole plant winds down: NC State Extension explains that pitcher plants go dormant in the fall, stay dormant until spring, and turn brown in the process ^[1]. Pitchers of S. purpurea, S. rosea and S. psittacina are longer lived than most, lasting up to two years ^[2].

What signals trouble is browning in the wrong place or at the wrong time:

The troubleshooter runs through the same checks.

Pitchers at the end of their life

How to check. Are the brown pitchers the older ones, while new pitchers and the growing point look healthy? That is ordinary turnover.

What to do. Trim with care. The ICPS points out that the plant recovers nutrients from old leaves for new growth, and that cutting off green leaves can starve a plant that does not have a large rhizome. Except in special cases, it cuts off only the brown part of each leaf. In spring, it also removes the tops of old pitchers and any leaf parts that could snag new flower stalks and leaves ^[2]. When you divide a plant, pull away all the old brown leaves at the base, because that thatch is a breeding ground for mealybugs ^[7]. Pitchers packed with rotting insects can be clipped off; the ICPS Pacific Northwest bog page does this partly to avoid attracting animals ^[8].

Seasonal die-back in autumn and winter

How to check. Is it autumn, and is the plant outdoors or somewhere with natural day length? Browning across the whole plant at this time is the start of dormancy ^[1].

What to do. The sources differ on when to tidy up, and the difference depends on where the plant spends the winter:

• Outdoors, unprotected: the ICPS leaves plants fully exposed to rain and snow and removes only dead leaves and brown leaf ends, unless a dense thatch builds up as it does in the S. rubra complex ^[2]. NC State Extension recommends waiting until spring, just before the flowers emerge, to remove the dead foliage ^[1]. Its S. flava page adds that in cold climates you can trim leaves back in winter as the pitchers die, cutting only dead tissue ^[9].
• In a garage, basement or cold frame: the ICPS recommends a fall haircut for the long-tube types, because old leaves out of the weather can harbor pests and reduce air circulation, inviting fungus ^[2]. Gray fuzz on stored leaves is covered in grey mold.

Plan the winter with the dormancy guide.

Heat and dry air

How to check. Did the browning follow a spell of very hot, dry weather? The ICPS notes that in areas with very high temperatures and low humidity, pitchers can burn ^[2]. Heat on its own is not the problem: the same guide says Sarracenia appreciate long growing seasons and warm to hot summers ^[2].

What to do. Give the plants some afternoon shade during the hottest part of the year, as the ICPS suggests, and make sure the water tray stays full ^[2]. Some species prefer afternoon shade anyway, according to NC State Extension ^[1].

The pot dried out

How to check. Has the tray or pot gone dry, even briefly? The ICPS says Sarracenia should never be allowed to dry out and that potted plants should always stand in about 4 to 6 cm of water. Its own trays are topped up every morning in the growing season, and it recommends an automatic watering system so the plants survive your absences ^[2]. Drought also compounds other problems; the ICPS rhizome rot page shows plants killed by salty water combined with drying out ^[4].

What to do. Refill the tray and remove the pitchers that have died back to brown. Note that NC State Extension also warns against the opposite mistake: pitcher plants tolerate occasional flooding but are not aquatic, and it calls keeping them too wet the biggest mistake ^[1]. The ICPS bog method fits both views, keeping the water level 7 to 18 cm (3 to 7 in) below the soil surface in an in-ground bog ^[2]; see the bog garden guide and water.

Salty water or too much fertilizer

How to check. What water do you use, and has the plant been fertilized? The ICPS deck-growing page says Sarracenia need a lot of water and that the leaves will show salt burn if it is too salty. Tap water is fine below 100 ppm total dissolved solids, or if you can collect plenty of summer rain ^[3].

Fertilizer causes similar damage. The ICPS sees little benefit in fertilizing the soil of mature plants ^[2], and its fertilization page recommends soil feeding only for juveniles ^[10]. For adults that catch nothing, the sources differ on pitcher feeding. The fertilization page prefers putting some dilute fertilizer into the pitchers ^[10]. The growing guide warns that fertilizer water put into long-tube pitchers is pumped into the soil, which defeats the purpose; it supports pitcher feeding mainly for the S. purpurea complex, using a slurry of dried bloodworms, and cautions that too much may burn the pitchers ^[2].

What to do. Switch to rain, distilled or reverse osmosis water if your supply is above the limit. If you have to use salty well water, the ICPS suggests leaching the salts often by watering from above and repotting more often ^[4]. See mineral burn.

Rhizome rot

How to check. Press the rhizome and look at the growing point. Soft, brown tissue and new growth that wilts are bad signs. The ICPS describes two routes to rot. Freeze damage turns the rhizome mushy in cold-sensitive species, most often S. psittacina, S. minor and S. leucophylla, when an early or late freeze hits plants that are not fully dormant. More worrying is a plant that dies in the growing season: weak fungi such as Rhizoctonia and Fusarium feed on dead leaf bases once fertilizer is added, or enter through root tips burned by fertilizer or salty water. A third pathogen, Cylindrocladium, makes a pitcher dehydrate and can kill the whole plant within two to three days; it spreads in water and has no cure ^[4].

What to do. Isolate the plant at once. Freeze-damaged plants can be saved if any part of the rhizome is firm and white: remove anything soft or brown and replant ^[4]. Full steps are in rhizome and root rot.

Frost on early growth

How to check. Did a frost arrive after the plant had started growing in spring, or before it went dormant in autumn? The ICPS warns that early and late freezes are what kill Sarracenia, while fully dormant plants in pots survive a few weeks frozen solid if they do not freeze-dry ^[2]. An Ontario grower profiled by the ICPS saw a light late frost damage early leaf growth and flower stalks ^[11].

What to do. Cover plants with row cover when a surprise freeze threatens, and pile snow on them in winter as insulation ^[2].

Pitcher plant moth caterpillars

How to check. Outdoors, look for a pitcher whose mouth has been closed with silk and which has a hole near its base. Caterpillars of the moth Exyra fax make that hole to drain the fluid, then eat the inner tissue and leave the outer skin as a shelter ^[6]. Related Exyra species feed in the pitchers of other Sarracenia ^{[12, 13]}. NC State Extension lists moth larvae among the pests to watch for, along with aphids, scale and mealybugs ^[1].

How much harm they do varies. In a Texas bog, about 86% of S. alata pitchers showed damage from E. semicrocea, and feeding by the moths reduced plant growth in a field experiment ^[12]. A study of E. ridingsii on S. flava found no effect on the next year’s growth ^[13]. These studies come from wild populations and do not address control in gardens. When you remove a damaged pitcher, follow the general rule and cut away the brown part ^[2].

Preventing brown pitchers

• Keep pots standing in water and never let them dry out; in a bog, keep the water level below the surface ^[2].
• Use water under 100 ppm TDS, or rain water ^[3].
• Do not fertilize the soil of adult plants ^[4].
• Give afternoon shade in very hot, dry climates ^[2].
• Choose species hardy for your area, and protect plants from early and late freezes ^[2].
• Quarantine new plants for a week or two before they join the collection ^[4].

Species details are on the Sarracenia genus page and in the profiles of S. flava and S. purpurea.