5 Ways to Save Your Tomatoes from Late Blight
Late blight is one of the more common fungal diseases that affect members of the Solanaceae family, of which tomatoes are a part of. Also referred to as potato blight, late blight’s official name is Phytophthora infestans. It is an oomycete, or “water mold” that contains devastating plant pathogens.
Late blight begins as grayish, greenish spots on leaves and as they grow they turn brown and rough. As this disease continues to grow and expand, eventually the plant will succumb and die. Because it is a fungal disease it can spread very easily through simple means such as wind moving the spores around over long distances, rain, or even through insect movement.
Unfortunately there is no absolute cure for late blight but there are a few good organic fungicides that you can use that have shown pretty good results. Your best method is to take these steps so you can reduce your tomato plants chances of getting late blight
TOMATO VARIETY
There are varieties of tomato plants that you can grow which have been shown to be effective against late blight; Defiant, Mountain Magic and Plum regal to name a few. Most of these tomato varieties are hybrids, so if you are a seed saver, they will not be a good choice for you. However, if you experience a lot of late blight, you may want to plant a few.
CHANGE LOCATION
Never plant your tomato plants in the same location in successive years. Fungal diseases can over winter under the right conditions and if it does, and if you plant your tomatoes in that same location, you are setting yourself up for disaster. In fact, you should not plant any member of the Solanaceae family in the same location.
WATER AT SOIL LEVEL
Wet leaves are a perfect environment for late blight, and if you water your tomato plants from above you are just inviting the problem in. Late blight has a hard time growing when the leaves are dry. To combat this, be sure to use soaker hoses and/or drip lines so that the water is going directly to the soil and not on the plant itself. Also be sure to keep your tomato plants elevated using cages or a trellis so that the leaves are not touching wet ground.
MAKE ROOM
Give your tomato plants plenty of room to grow. This allows air to flow through the plants which helps keep tomato leaves dry. The key here to all of this is to make sure your tomato plants stay dry.
AVOID THE COMPOST PILE
If you have tomato plants that have been infected with late blight, your best bet, when the plant eventually dies, is to throw it away in your normal trash as opposed to throwing it in your compost pile. Throwing your infected plant into your compost pile may allow the disease to overwinter and be carried through your garden when you eventually mix in your finished compost.
While none of these tips are cure alls for late blight, by combining all them you can greatly reduce your chances of your tomato crops being wiped out by this destructive plant disease.
About the Author
Mike Podlesny is the author of the book Vegetable Gardening for the Average Person as well as the creator of the Seeds of the Month Club where members receive non gmo, heirloom variety seeds every month. You can listen to Mike each week on the Vegetable Gardening Podcast where he interviews gardening industry experts.
I learned about not planting tomatoes in the same spot each year a few weeks back and likely why we got nothing last year. We didn’t bother this year to plant since our families both have huge gardens. We did however notice that we lost our basil as the leaves turned a dark colour and died off. The basil was in immaculate condition until my wife watered them with the hose. I suspect she watered from the top and not in the soil. I also have a honeysuckle plant that fires off great at the beginning of the season then it gets coated in a white fungus. I don’t know what is wrong but I just want to rip it out now. I built a trellis for it a few years back and it’s hardly growing. The previous owner had planted it so it’s got years behind it so something is wrong.
Ugh Mr. CBB I hate gardening problems……interestingly we planted two different types of basil in my herb garden one did amazingly well and the other did awful…..that is strange about your honeysuckle…should just go rampant it does her in NC! It is difficult to kill certain things in NC however it is very easy to get blight, fungus, rot etc….because of all the rain we get! Thanks for your comments!