Now that cold weather is approaching, we must think about helping our trees transition into winter. This is also called overwintering.
Citrus trees are fairly easy to prepare for winter. For those in the Mid-West and on the East Coast, you should bring your trees inside to protect them from frost. For those who live on the west coast, a light frost cover will do if it gets close to freezing at night.
Here are some tips if you plan to bring your trees inside for the winter:
- In the beginning of autumn, move your trees to a shaded outdoor spot for several weeks. This will help them to acclimate to the change in weather.
- Before bringing your trees in, check them for insects. Spray the foliage and trunk thoroughly with water and allow the plant to drip dry. Treat the tree with insecticidal soap and pick off any bugs you may have missed. Aphids and scale are common indoor citrus pests. The soap will kill most pests on contact. Throughout the winter, continue to look for signs of aphids and scale. Lightweight oils and insecticidal soaps will help control them.
- Move the trees to a south-facing window or a bright room where they will receive maximum light. A temperature range between 55 and 68 degrees F is ideal. Keep them away from heating vents or drafty areas.
- Citrus trees require humidity, so you should provide a supplemental form of humidity. This is important, especially when the plants are in bloom. If it is too dry, they will not hold onto their blossoms.
- Place a shallow container of pebbles under the pot to give the plant the extra humidity. Partially cover the pebbles with water- the pot should never sit in water.
- Reduce watering during winter months and water only when the soil is dry to the touch.
- Do not fertilize your tree during the winter months.
- In spring as it gets warmer, gradually introduce your plants to outdoor conditions.
Here are some tips if your tree is outside in the winter:
- Pick the ripe fruit before the frost hits.
- Water outdoor citrus trees during the winter to protect the roots from damage. Moist soil freezes but will not harm the roots. Give young trees about 1-2 gallons of water weekly November through February in the absence of rainfall. Give more mature trees up to 5 gallons weekly between November and February if it is a dry winter.
- There are also frost cloths available to cover your tree. You can also wrap the tree’s trunk in layers of cardboard to insulate it against frost. Cover the trunk from just below the main limbs to the ground. Secure the cardboard with duct tape. Leave it in place until the last frost.
- String small outdoor holiday lights throughout the tree’s branches to help warm them before frost hits.
- Watch for aphids and scale. Knock them off with a spray from the garden hose. Treat the tree with insecticidal soap as needed.
- Wait to prune until after the last frost for your area.