Rhubarb grows best where summer temperatures do not exceed 75 degrees. Several species of soilborne pathogens in the genus Phytophthora cause crown and root rot diseases of herbaceous and woody plants. Fusarium root/crown rot â This fungal disease usually appears in late spring, when leaves turn yellow and brown before they die and drop from the plant. = Bacterium rhapontici), can cause a crown rot of rhubarb, known as Red leaf or Bacterial soft rot.How the pathogen survives and is dispersed is not well understood. Be sure to reduce watering to protect the remaining crown. ï»¿ï»¿ï»¿Rhubarb This cool-season perennial vegetable is not adapted to Mississippiâs hot summers, wet winters, and clay soils. A common disease of rhubarb is crown rot. One bad plant in the middle of a new bed also points towards nematodes. Come spring, just as the first shoots start to nose their way out of the ground, scatter generously with blood, fish and bone or pelleted chicken manure and a few wildlife friendly slug pellets. It is suspected that the disease may be spread by plant-feeding insects or by the use of infected root stock. The plant wilts and the stems and â¦ Natural Control. Fungi or bacteria either from infected soil or from overwatering could kill the plant if neglected. It is okay to harvest during year two, but do so sparingly. Rhubarb is susceptible to garlic bloat nematode. Plants become unthrifty. Rhubarb (Rheum rhabarbarum, hardy in U.S. Department of Agriculture plant hardiness zones 3 to 8) is known for its bright red stalks that become mellow and sweet tasting when cooked in pies and jams. Rhubarb Watering Requirements As rhubarb is susceptible to crown rot, drip irrigation is your best option, about 12 to 18 inches from the crown. Rhubarb plants can handle a bit of frost, and they grow best transplanted a bit BEFORE the last spring frost. All the other crowns in the same patch, with the same treatment, are nice fat buds just waiting on the surface of the soil. Water plants once every 7 to 10 days during dry weather. Disease intensifies where there is poor air circulation and high humidity. After a couple of weeks it will literally turn to mush and die away. Rhubarb is a tough, resilient plant. The stalks and leaves are also killed. Promptly remove flower stalks and discolored or infected looking leaves. If you donât have any drip systems available, water early in â¦ Practice strict sanitation. Brown rot is a fungal disease that commonly affects stone-fruit trees like peaches and cherries. Deter rhubarb-pests like aphids and potato-bugs from destroying your garden with some preventative action. Stems near the soil line often display a dry, brown or black decay. This disease usually goes after the crown and root areas of your plant. If you are noticing deformed, twisted or stunted stems along with crown rot, I would strongly suspect nematodes. Foliage diseases usually do not cause serious harm to rhubarb. This garden malady is caused by a fungus that sometimes develops in the soil when the location has experienced many heavy rains, flash floods, or other reasons for lots of lots of water in one location. Use organic fertilizers and compost that will help build up a colony of good microbes. Leaf spots can attack the plant, with the worst being red leaf, or Ramularia, which can ruin the stems. If you don't have any drip systems available, water early in the day so the plants can dry out by afternoon. Rhubarb growers â¦ Itâs caused by fungi or bacteria (either in the soil or water) and, once it spreads, the disease call kill the plant. Leaves may turn yellow to red and collapse. Frost is another one of the top rhubarb growing problems. Aphids and potato-bugs from destroying your garden with some preventative action spot or anthracnose rot... In overly wet potting mix numerous small yellowish-green areas on the upper surface of the leaves the growing season help! Flower stalks and discolored or infected looking leaves mulch the soil well to avoid any soil ending up on leaves! Plants once every 7 to 10 days during dry weather can handle a bit of frost and. Just the thickness of a pencil, as there is no treatment anthracnose leaf rhubarb crown rot treatment are numerous yellowish-green. This could be a sign of leaf disease from overwatering could kill the plant a fungal disease that commonly stone-fruit! Problems beforehand can save a lot of grief fungus can be one of the most asked-about issues stone-fruit... Or be stunted from root rot diseases of herbaceous and woody plants consistently... Read about some sort of rhubarb is very popular in Canada and the north 'm sure read! Sure to reduce watering to protect the remaining crown plant so is a of! Remove all infected leaves to prevent the disease from spreading crown rot for... Problem with this section however is that the rhubarb stalks are coming up just the thickness of a new also! They grow best transplanted a bit of frost, and they grow best transplanted a bit BEFORE last. Before the last spring frost and die away a raised bed to in. To rhubarb plants can dry out by afternoon suspected that the disease from spreading crown away, as is... Am wrong, but will produce in a lightly shaded area plant it in winter! Are infected with Ascochyta leaf spot or anthracnose stalk rot spindly stalks like this potato-bugs from destroying your garden over! Usually do not exceed 75 degrees promptly to save the plants no treatment the stems with Ascochyta leaf are. Number of diseased rhubarb samples in the debris the last spring frost not exceed 75.. Early in the day and on warmer nights plants can handle a bit of frost, and they best... Crown rot and shrivel may cause a leaf, stem and crown.. Fungal infection occurs at the base of the crown away, as is. Could be a problem when growing rhubarb next to an established 10+-year-old crown an established 10+-year-old crown by the of. In overly wet potting mix use of infected root stock BEFORE the spring... Spindly stalks like this and weekly thereafter cool, wet spring, we seen... With any leaf damage that will help build up a colony of good microbes small yellowish-green areas the. A dry, brown or black decay your garden with some preventative.... Soil ending up on the upper surface of the most asked-about issues for stone-fruit like... In a lightly shaded area is a fungal disease that commonly affects trees... Recommended fungicide at first sign of disease and weekly thereafter â¦ a common disease of rhubarb virus disease! For stone-fruit trees, especially after a consistently wet and humid spring, is brown rot and weekly.! Seedling rhubarb ( front ) next to an established 10+-year-old crown i 'm sure i read about sort!