Plant Care
Updated Feb. 2023
Warm Soil in Winter:
Cold soil inhibits growth of indoor citrus trees. As with outdoor plants, when the soil begins to warm in spring, new growth emerges. To help with new and continued growth year-round with citrus trees, keep soil warm by elevating the pot from a cold floor or away from cold drafts. In an especially cold room, a small heating pad may be used underneath the pot (on lowest setting) to keep the soil in optimal growth mode.
Spring Note:
If you wish to move your tree outdoors for summer keep these details in mind: Give your tree a place out of the wind, and acclimatize it slowly to sunlight to prevent leaf drop by setting it out only a couple hours at first and increase the hours each day. Also, to begin with, do not set your tree outdoors during the hottest part of the day - morning or evening sunlight is not as harsh as mid-day. Moving your tree back indoors in the fall is done the same way. Monitor outdoor temps as they begin to drop in Sept, moving tree inside when temps dip below 10 degrees Celsius. Keeping trees outside in summer provides for the humidity needs of citrus with the dew and rain. Pests management is the same outdoors as indoor care, except you may need to apply the insecticidal soap spray more often on leaves and soil.
When your tree arrives in the mail:
The tree comes in it's own black fabric grow pot and DOES NOT need to be re-potted into a larger fabric pot until the date specified on your quote.
Purchase a larger decorative pot (no need for holes in the bottom of this pot) to set the fabric pot inside of, with a few inches of air space between the decorative pot and the fabric grow pot. Also, elevate the black fabric grow pot from the bottom of larger decorative pot, so it will drain water away from roots and breathe.
They grow quite fast in these fabric pots and are developing large root zones because oxygen can access the roots from all sides.
PLEASE read through your CITRUS TREE CARE sheet which will be enclosed (both sides).
The day your tree is shipped from our greenhouse it was treated with the following:
1). Insecticidal Soap spray. Calculate the next date tree will need to be sprayed as 2 weeks from arrival date, and then every 2 weeks after that, year-round.
Insecticidal Soap spray (any brand) which can be purchased from most garden centers (IT IS NOT INCLUDED IN YOUR ORDER).
Do not use "END ALL" or products that are a miticide or acaricide, as these are too strong to use on citrus trees.
2). Slow release pellet fertilizer. Calculate 6 weeks for when the next application is needed (these pellets are included in your order).
Continue to follow instructions on the pellet package.
3). Foliar Spray Fertilizer. Calculate the next date for foliar spray application on the leaves as 3 weeks to one month from tree arrival date.
Foliar Spray is in our fertilizer kit (available to local customers only) however we do provide a foliar spray formula below.
4). Seaboost has been added with the last warm watering, the day your tree was shipped. This will help the tree settle into its new environment.
Seaboost (a Nova Scotia product) can be added this way to one watering per month, all year round.
When you open your box, place your tree in a sink and water well with warm water - rinsing the leaves as well.
Now place tree near a window area with indirect sunlight for the first few days, and transition to direct sunlight a few hours per day. If you wish to move it outdoors in summer, please do this gradually as well. Remember sunlight has UV rays that the leaves of plants are protected from when inside, therefore treat as you would your own skin - an hour a day for first few days, then slowly add more time. Bring indoors for any temperatures below 15 degrees. Keep out of direct wind to protect from wind damage.
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Sun: Indoors, in winter months require placing your potted citrus tree near a south facing (or sunniest area you have) window to give it as much sunlight as possible - even 3 hrs is adequate. Grow lights may be needed it there is not enough consistent sunlight. In Canada, forced air heating can often be installed near large south facing windows; DO NOT place your tree near this type of blowing hot air.
Our Northern Style greenhouse: is only south facing, with North side completely insulated from light and cold. This allows our trees to grow with a sun exposure which most home owners can mimic with their own south facing windows in our local climate zone. Most of our heat is passive solar: heat from the sun stored in gravel floors and insulation. We do use a ceramic heater and ceiling fan to circulate warm air when temperatures drop to zero, as well as a humidifier that runs a few hours, once per week. Coldest night time temperatures are maintained at no lower than 10 degrees Celsius, which means a customers home environment need not be kept at typical commercial greenhouse temperatures of 20 degrees or higher.
Humidity: Indoors is also a dry environment because of forced heating (electric, wood, oil, air, etc), therefore your tree should be given some extra humidity. A simple way to accomplish this is to place a bowl filled with pebbles immersed in water, next to (not under - as extra moisture is not wanted near root system) your tree. As water evaporates it provides humidity to your tree. Misting it's leaves with distilled or rain water can also helpful, but only once every week and never in direct sunlight. Another simple solution is to purchase a small humidifier which produces cool mist. Some of these are quite small requiring very little electricity (ultrasonic humidifier).
Fertilizer: Our trees are sold when 2 years old; at the stage of pushing forth first flowers and setting first fruit. This makes them heavy feeders, as their root system is much larger than the plants appear. There are a few choices you can make to meet this need. We offer our own slow release pellet fertilizer and foliar spray fertilizer, as your first choice as these are the products already being used on our trees, with success. If you do not have access to our fertilizers then you may choose a liquid plant fertilizer with every second watering ONLY during warmer, faster growing weather and when fruit has formed.
Fruit
SeaBoost (www.seaboost.ca/products/seaboost) is quickly absorbed by root zones . It is a Nova Scotia product, sourced across Canada in garden centers, which we have been using since 2019. We recommend it over all other liquid fertilizers to supplement the fruit bearing season. Even through winter we have added it to one watering a month with wonderful success. Use: 4 ml SeaBoost to 250 ml warm water and mix well before using.
Slow release pellet fertilizer are always needed. With each watering of warm water, these pellets dissolve and release nutrients which keep the soil slightly acidic which enables the roots of citrus to uptake nutrition. If the soil is alkaline it will not be able to take up nutrients. We use Nutricote 18-6-8 pellets.
When using our slow release pellet fertilizer, place one Tablespoon of pellets around the perimeter of small 6" tree pots every 3 months or 2 Tablespoons for larger trees; keeping it away from root zone or trunk of the tree. If you do not have access to our slow release pellets, purchase slow release for Rhododendrons & Azaleas from your local garden center.
Foliar fertilizer sprays with calcium, magnesium and micro-nutrients are extremely helpful to citrus in orchards and in pots, as the leaves rapidly respond to this form of fertilizer. These foliar sprays are very difficult to source in Canada, however, as previously stated, we are able to provide both slow-release pellets and micro-nutrient foliar spray fertilizers in small quantities with the sale of our trees. If you overuse foliar spray you can "burn" the leaves. You will notice a regular green leaf with a dark yellow beginning to appear around the edges of some leaves, if this happens. This leaf will eventually need to be cut off, but wait until new leaf growth appears on your tree before pruning.
This is our Foliar Spray instructions on chelated micro-nutrient mix included in our fertilizer packs that are mailed out. Our Farm Shop provides pre-mixed foliar spray in a spritzer bottle, with a calcium component.
Foliar Spray
Step 1: Dissolve ½ teaspoon Epsom salts in ¼ cup hot water
Step 2: In 500 ml warm water, dissolve ¼ teaspoon chelated micronutrients (any brand).
We use: www.plantprod.com/product/plant-prod-chelated-micronutrient-mix/
Step 3: Blend both mixtures together to form ‘Foliar Spray”. Spray onto leaves every 2 or 3 weeks at night.
Mycorrhiza is added to our soil mix whenever repotting. Check out this video link to see why this ingredient is so important to all soil composition:
https://www.youtube.com/watch?v=0oyqPZJj-2w&ab_channel=DownToEarthFertilizer
Magnesium Sulfate vs Aluminum Sulfate : Aluminum sulfate is often recommended to acidify soils for acid loving plants like rhododendrons, azaleas, etc and can be added in a small dose to your watering routine (as directed on it's label) every 6 months, or when needed, and it does help correct the ph in citrus soil - keeping it acidic NOT alkaline. However, it can also 'burn' roots of potted plants if used in excess. Increasing the Magnesium Sulfate (dissolved epsom salts) works much better than aluminum sulfate.
Humic Acid: is also a good additive, in small quantities, to one watering per month.
Watering: ALWAYS USE WARM WATER. Citrus do not thrive with wet roots. Do not over water. With the desire to see more growth, sometimes it is easy for new owners to over-water citrus. Every home environment has a different heat source, humidity level and air movement factors. During the first 2 weeks the tree soil should be monitored to see how long it takes to dry out - not completely dry - but to the point that watering is optimal. To test the soil, place a finger into the top inch of the soil, if it is damp, do NOT water. Keep testing each day until soil begins to dry and show signs of slightly pulling away from side of pot (this is the small pot size our trees are sold in. If the tree has been transplanted into a larger pot - watering times will be longer in between). Another sign is the color of the perlite within the soil mixture begins to turn darker brown (when wet, these particles are white). It is imperative to soil check for the first few waterings until the new owner is confident the plant is able to have adequate time to dry out between them. Fabric pots work the best for consistent drainage and root development.
How much water: Our plants are sold in 6 inch diameter pots and require up to 2 cups of warm water spaced at intervals of 3 - 5 days depending on daytime temperatures. Larger trees which are transplanted into our larger fabric pots (14"- 18" diameter) will need at least 2 cups and up to 1 liter of warm water spaced at intervals of 7 to 14 days depending on daytime temperatures.
The simplest way to enable your tree to absorb the water it needs is to NOT water from the top, but to fill a sink or bucket with warm water and set the fabric pot within the bucket until the water rises to 2" below the top soil line. Hold the pot in this position for 30 - 45 seconds while the water is absorbed through the sides and bottom of the pot. Often the top of the soil remains dryer with this method and keeps fungus gnats from setting up home in top of your soil.
As water is heavy, you will feel the weight of your fabric pot increase, pull it out of the water and allow to drip freely in a sink for 30+ minutes.
If using liquid fertilizers a few times per years during heavy growth seasons (summer), simply mix rainwater or distilled water with recommended amount of liquid fertilizer (this info will be on fertilizer pkg) for 1 cup of water - allow few moments for mixture to dissolve then slowly pour onto the soil, NOT onto the plant leaves. Setting your pot in a sink or large bowl is helpful, as you want excess water to drain out the bottom holes .
If you are growing your tree in a solid pot (NOT a fabric grow pot) your watering amounts will be less and intervals between waterings will be longer, as these type of pots take much longer to dry out.
Water Source: Some city water or water sources may contain chemicals that can hinder proper growth of your tree - it may be wise to simply use distilled or rainwater.
Re-potting: Never add soil to the top of the 6 inch pot your tree comes in from our farm. The soil mix is perfect for this time in your trees' life and also the top part of the root ball must stay exposed to air, as burying it with soil is choking your plant. Depending on the time of year you have purchased a tree from our farm will depend on when we recommend re-potting. Trees we sell in spring and early summer we recommend keeping in the fabric pot it was purchased in until the Fall or even until following spring, depending on how much growth it is producing.
We recommend using a 1 or 2 gallon fabric pot for repotting. We sell this size fabric pot or you can purchase a fabric pot from another source. Although we have experienced fabric pots to be the best, if you do not have one, you can also use an inexpensive black plastic pot with drainage holes in the bottom, just above the bottom sides of pot. In each case, set the plant and its pot within an even larger, heavier decorative pot, providing a few inches between the inner pot with the tree and the heavier pot.
Soil Mix: We sell our own Citrus Soil Blend to re-pot trees from our farm. This blend includes 25% coir (re-hydrated coconut husks), 50% aged bark mulch (5+ years old and turning black as it decomposes), 10% perlite, 10% black earth or potting soil, 5% sand and mycorrhiza. Do not use premixes with 'wetting agents' as these can harm the roots. The goal of the soil blend is to have a mix which allows water to pass easily through the roots and not become soggy. If soil appears compact, and leaves drop, make sure your watering thoroughly enough and allowing proper time for mix to dry out before re-watering.
Why we use mycorrhiza? Check out this video link to see why this ingredient is so important to all soil composition:
https://www.youtube.com/watch?v=0oyqPZJj-2w&ab_channel=DownToEarthFertilizer
Canadian garden centers often have African Violet Mix and Orchid Mix which have some of these ingredients.
Also coconut coir bricks are available for the indoor hydroponic growing, as well as small bags of perlite.
Another soil mix that is close to our own and is more readily available to customers across Canada is this (1.4 kg or 9 L) Premium Potting mix: Pro-Mix with mycorrhiza.
https://www.homehardware.ca/en/9l-potting-and-container-soil-mix/p/5053610
Remember to never add too much of an ingredient that will cause soil mix to be too alkaline, such as lime.
Citrus soil needs to be kept slightly acidic for the roots to utilize the nutrients in the soil.
Fill new pot with a new soil mix, and water it. Make an imprint into this soil with the pot you are taking your tree from, as you will need this exact size hole to place tree in. Cut sides of old citrus tree pot to gently remove the tree and soil. Check for any type of root rot; trim off any slimy feeling roots, as these have rotted from soil that was kept too wet. Set tree root-ball into center of pot and gently firm more soil mix around perimeter.
Again, make sure to place soil only as far up the trunk of the tree as the previous soil layer - leaving at least 1/4 inch of the root-ball exposed to air. After tree settles for 2 weeks, then sprinkle pellet fertilizer 1 tsp, around perimeter of pot - away from root zone and water. Place this new pot within a yet larger fashionable pot of plastic, clay, etc, leaving a few inches of air space between the outside surface of the fabric pot and the solid pot. This is helpful because it allows a few inches of air insulation for your tree - keeping it cooler in summer (less evaporation) and warmer in cooler months.
Pest Management: It is VITAL to use the same proactive schedule we do in our citrus greenhouse to keep harmful bugs off citrus trees.
Use 'Insecticidal Soap Spray" every 2 weeks (or more if needed), on leaves, stems and even soil. Apply this at night when sun is not shining on leaves, and rinse residue off with clear warm water after it has dried (1 - 2 hrs after application). Do not depend on homemade forms of this spray using dish detergent, as detergents only clean the tree and do not harm pests. Insecticidal soap is a product available at Home Hardware or Home Depot to deal with spider mites, aphids, mealybugs, thrips, whiteflies which may irritate your tree at some point in it's life. The fatty acids in insecticidal soaps break down the protective cuticles of soft-bodies pests so they quickly dehydrate and die. Green Earth Horticultural Oil, is also an ideal product to kill scale insects, mealy bugs, mites...etc.
Do not use "END ALL" or products that are a miticide or acaricide, as these are too strong to use on citrus trees.
Pruning: Do not allow any new growth below the lowest branch or the lowest leaves that are now growing on your tree. Do not be afraid to prune long branches as this will cause new growth to develop lower down on the stem, with the purpose of creating a more full canopy of branches and leaves.
Anytime leaves look damaged, sickly or dying: cut the leaf off from the branch, leaving a 1/4 inch of leaf stem remaining on the branch.
New growth usually develops at the junction of these leaf stems and the trunk.
Diseases & Disorders of Leaves & Twigs in Citrus:
Leaf drop: One of the most common issues with indoor citrus trees is leaf drop of a few or even all of the leaves! This usually happens because of a sudden change in the trees environment: exposure to extreme cold or heat, undetected pests irritating the leaves, overwatering causing the roots to begin to rot, underwatering causing leaves to dry up.
Leaves can also drop from slow changes once it leaves our greenhouse - continuous exposure to less and less sunlight, continuous overwatering or underwatering and continuous
neglect of pest management. BUT do not be discouraged citrus tree roots are tough! Our citrus trees already have root zones that are at least 2 years old and quite hardy, even if they have lost all their leaves. If your leaves drop for the first time - investigate where you went wrong (overwatering - then allow soil to dry more thoroughly, elevate from the bottom to allow better drainage, etc) and correct the issue. Watch for new growth at the bud points where former leaves grew. Please use this PLANT CARE tab as a means of comparing the care of your tree to how we have learned to care for ours, as a means of pinpointing how to correct your trees environment.
Graft Die Off: Our citrus trees are grafted. This means lower citrus variety (root stock) is grown from seed and after a year's growth, it is cut off 6" above soil line and a specific citrus fruit variety (Meyer Lemon, Keifer/Makrut Lime, etc) is grafted on as a bud graft. This union enables the roots to support the specific fruit we humans are interested in. Where the root stock and the citrus fruit bud is attached is called the 'graft union', and it is quite noticable at approx. 6 " above the soil line.
Once this bud graft grows several inches tall with several leaves, it is ready to flower. Usually this whole process from seed to graft, to ability to flower takes 2 years. After this time, if a tree has major struggles in its care or growing environment and looses all it's leaves, its branches turn brown and die, and even the main trunk turns brown and brittle down to the graft union, then the only life remaining will be that of the original citrus variety used for it's roots, not for it's fruit. This root citrus can grow extrememly fast but will not produce viable fruit. The owner can throw the plant away or try to re-graft buds from another fruit producing citrus tree.
Resources:
Check out this link from University of California to help learn to identify potential issues with citrus trees.
Remember potted citrus trees (in Canada) are not going to have as many diseases and insect infestation as orchard trees grown in much warmer climates.
http://ipm.ucanr.edu/PMG/C107/m107bpleaftwigdis.html
Happy Growing......