Yellow, spotted leaves, and mushy fruit are common issues for potted tomatoes, especially in late summer. Plant your tomatoes correctly and avoid these issues altogether!
- Incorrect Pot: Tomatoes have big root systems, and no amount of extra water or fertilizer will substitute for lack of space for the roots. I recommend a large tree pot. Five-gallon buckets are not large enough to have a happy tomato all summer. Once the roots grow to the sides of the pots, they are easily burned by the heat of the sun. You’ll notice this from excessive wilting, as well as dry edges and yellowing on the leaves. Ten to fifteen-gallon pots are best. Make sure that the pots have drain holes on the bottom. Sopping wet roots aren’t good for any plant unless it’s from a bog! Too wet or too dry can cause leaves to yellow and flowers to fall off without making fruit. The bottom end- rot is when the tip of your fruit turns brown and mushy. This is often contributed to a lack of calcium, but most likely in these parts it’s caused by improper watering, since our Deer Park and Elk water has adequate calcium already. Make sure water runs out the bottom of the pot every time, and then allow it to dry 1/3 of the way down before watering it again.
- Poor Potting Soil: Compost and potting soil mixed together is the best way to provide a healthy substrate for your tomato. Look for good organic potting soil. Make sure it says ‘potting soil’ and not ‘raised bed soil’, ‘garden conditioner’, or ‘top soil’, which are good for in-ground or raised beds but not meant for pots. Potting soil is formulated for good drainage as well as moisture retentiveness. Mix ½ and ½ potting soil and compost, and you’ll find it to be an excellent combination for growing all your potted vegetables organically without the use of chemical fertilizers.
- Wrong Location: It is tempting to push pots up against the wall of the house, but this can lead to damage from rain run-off from the roof, disease from lack of air movement, and either poor light from overhanging eaves or burning from reflective heat and light off the wall. Place tomatoes out where they can receive lots of light and plenty of air movement. If your location is only partly sunny, choose tomatoes that can tolerate some shade, like Mountain Fresh, Mountain Merit, or Sub-Arctic Plenty.
- Wrong Tomato: Look for determinate tomatoes rather than indeterminate. Determinates are short and stalky by nature, whereas indeterminate varieties want to grow very tall and need staking so the branches don’t break! Good Determinate varieties are Legend, Black Krim, and Cherry Falls.
Photo By Karolina Kolodziejczak