In the middle of January, not a lot is going on outside in the home landscape except the feeding stations, kept full of seed and suet for birds, cobs of corn for the squirrels and maybe a salt lick for other kinds of wildlife. Perennial beds covered in leaves or snow enjoy the protection from drying winter winds and the sun (if we see sunny days).
Inside the home is a bit different. Depending on your level of outdoor vegetable and flower gardening, there are catalogs to go over and lists to be made of seeds to be ordered. If part of that winter gardening includes growing your own transplants, additional supplies may be needed like seedling flats or trays, heating mats, and soilless media to start the seeds. These too can be ordered online. If a gardening fix is needed, make a trip to your favorite garden center or greenhouse.
Just a reminder on starting seeds indoors: read the seed packet label and do not start those seeds too early! It is good to order the seeds and supplies early so they are there when it is time to sow them. The label also will provide instructions for the proper way to germinate those seeds. Keeping the seeds too wet is often a downfall.
Gardening indoors this time of year also includes keeping those houseplants healthy. In the darker days of winter (and by the way, we just passed the half-way mark) watering changes as those plants are just maintaining and not really growing. It is very easy to over-water and cause root rots in the pots. Clay pots are more forgiving but also dry out quicker as they are porous. Plastic pots do not breathe and the only route the water has is through the bottom drainage holes which can often times be blocked by circling roots.
Houseplant insects tend to be another problem. When set outside for the summer, the wind, rain and predator insects keep them in check. In the winter indoors, none of those conditions exist and houseplant insect populations really can explode. One of more common insects is the spider mite. When the infestations are bad, you can see webbing at the margins of the leaves and down in the axils where the leaf attaches to the stem. Another visual clue is that the margins of the leaves will yellow and brown due to the mite feeding on the tender cells at the edge of the leaves. Putting the plants in the sink or tub and using a strong force of water to dislodge the insects works well. You also should wipe down both sides of the leaves with a wet paper towel. (If needed, a spray of insecticidal soap also can be used.) These mites are very small and easy to miss, so your chosen method will need to be repeated in a week or two and until no evidence of new feeding can be seen.
One last thought. If you have spring fever, look for gardening-themed events happening this winter. You can find upcoming events or educational sessions from University of Illinois Extension at https://extension.illinois.edu/global/events